Advanced Data Structures Introduction to Data Structures Data Structures: A data structure is an arrangement of data in a computer's memory or even disk storage. Data structures can be classified into two types Linear Data Structures Non Linear Data Structures Linear Data Structures: Linear data structures are those data structures in which data elements are accessed (read and written) in sequential fashion ( one by one) Eg: Stacks , Queues, Lists, Arrays Non Linear Data Structures: Non Linear Data Structures are those in which data elements are not accessed in sequential fashion. Eg: trees, graphs Algorithm: Step by Step process of representing solution to a problem in words is called an Algorithm. Characteristics of an Algorithm: 1 Input : An algorithm should have zero or more inputs Output: An algorithm should have one or more outputs Finiteness: Every step in an algorithm should end in finite amount of time Unambiguous: Each step in an algorithm should clearly stated Effectiveness: Each step in an algorithm should be effective Advanced Data Structures Characteristics of Data Structures Data Structure Advantages Disadvantages Array Quick inserts Fast access if index known Slow search Slow deletes Fixed size Ordered Array Faster search than unsorted array Slow inserts Slow deletes Fixed size Stack Last-in, first-out acces Slow access to other items Queue First-in, first-out access Slow access to other items Linked List Quick inserts Quick deletes Slow search Binary Tree Quick search Quick inserts Quick deletes (If the tree remains balanced) Deletion algorithm is complex Red-Black Tree Quick search Quick inserts Quick deletes (Tree always remains balanced) Complex to implement 2-3-4 Tree Quick search Complex to implement Quick inserts Quick deletes (Tree always remains balanced) (Similar trees good for disk storage) Hash Table Very fast access if key is known Quick inserts Slow deletes Access slow if key is not known Inefficient memory usage Heap Quick inserts Quick deletes Access to largest item Slow access to other items Graph Best models real-world situations Some algorithms are slow and very complex 2 Advanced Data Structures Stack : Stack is a Linear Data Structure which follows Last in First Out mechanism. It means: the first element inserted is the last one to be removed Stack uses a variable called top which points topmost element in the stack. top is incremented while pushing (inserting) an element in to the stack and decremented while poping (deleting) an element from the stack A top Push(A) B A Push(B) C B A top top Push(C) D C B A Push(D) top C B A Pop() Valid Operations on Stack: Inserting an element in to the stack (Push) Deleting an element in to the stack (Pop) Displaying the elements in the queue (Display) Note: While pushing an element into the stack, stack is full condition should be checked While deleting an element from the stack, stack is empty condition should be checked Applications of Stack: 3 Stacks are used in recursion programs Stacks are used in function calls Stacks are used in interrupt implementation top Advanced Data Structures Queue: Queue is a Linear Data Structure which follows First in First out mechanism. It means: the first element inserted is the first one to be removed Queue uses two variables rear and front. Rear is incremented while inserting an element into the queue and front is incremented while deleting element from the queue B A rear front A Insert(A) Insert(B) rear front C B A Insert(C) rear front D C B A Insert(D) rear D C B front Delete() Valid Operations on Queue: Inserting an element in to the queue Deleting an element in to the queue Displaying the elements in the queue Note: While inserting an element into the queue, queue is full condition should be checked While deleting an element from the queue, queue is empty condition should be checked Applications of Queues: Real life examples Waiting in line Waiting on hold for tech support Applications related to Computer Science Threads Job scheduling (e.g. Round-Robin algorithm for CPU allocation) 4 rear front Advanced Data Structures Linked List: To overcome the disadvantage of fixed size arrays linked list were introduced. A linked list consists of nodes of data which are connected with each other. Every node consist of two parts data and the link to other nodes. The nodes are created dynamically. NODE bat Data link bat cat Types of Linked Lists: Single linked list Double linked list Circular linked list Valid operations on linked list: 5 Inserting an element at first position Deleting an element at first position Inserting an element at end Deleting an element at end Inserting an element after given element Inserting an element before given element Deleting given element sat vat NULL Advanced Data Structures Trees : A tree is a Non-Linear Data Structure which consists of set of nodes called vertices and set of edges which links vertices Terminology: Root Node: The starting node of a tree is called Root node of that tree Terminal Nodes: The node which has no children is said to be terminal node or leaf . Non-Terminal Node: The nodes which have children is said to be Non-Terminal Nodes Degree: The degree of a node is number of sub trees of that node Depth: The length of largest path from root to terminals is said to be depth or height of the tree Siblings: The children of same parent are said to be siblings Ancestors: The ancestors of a node are all the nodes along the path from the root to the node A C B D E F G H 6 I Property Number of nodes Height Root Node Leaves Interior nodes Number of levels Ancestors of H Descendants of B Siblings of E Value : : : : : : : : : 9 4 A ED, H, I, F, C D, E, G 5 I D,E, F D, F Advanced Data Structures Binary Trees: Binary trees are special class of trees in which max degree for each node is 2 Recursive definition: A binary tree is a finite set of nodes that is either empty or consists of a root and two disjoint binary trees called the left subtree and the right subtree. Any tree can be transformed into binary tree. By left child-right sibling representation. A B C E K F G D Binary Tree Traversal Techniques: There are three binary tree traversing techniques Inorder Preorder Postorder Inorder: In inorder traversing first left subtree is visited followed by root and right subtree Preorder: In preorder traversing first root is visited followed by left subtree and right subtree. Postorder: In post order traversing first left tree is visited followed by right subtree and root. 7 Advanced Data Structures Binary Search Tree: A Binary Search Tree (BST) is a binary tree which follows the following conditons Every element has a unique key. The keys in a nonempty left subtree are smaller than the key in the root of subtree. The keys in a nonempty right subtree are grater than the key in the root of subtree. The left and right subtrees are also binary search trees. 63 89 41 34 56 Valid Operations on Binary Search Tree: 8 Inserting an element Deleting an element Searching for an element Traversing 72 95 Advanced Data Structures Avl Tree: If in a binary search tree, the elements are inserted in sorted order then the height will be n, where n is number of elements. To overcome this disadvantage balanced trees were introduced. Balanced binary search trees An AVL Tree is a binary search tree such that for every internal node v of T, the heights of the children of v can differ by at most 1. 4 44 2 3 17 78 1 2 32 1 88 50 1 48 Operations of Avl tree: 9 Inserting an element Deleting an element Searching for an element Traversing Height balancing 62 1 Advanced Data Structures Graphs A graph is a Non-Linear Data Structure which consists of set of nodes called vertices V and set of edges E which links vertices Note: A tree is a graph with out loops 0 0 1 1 2 2 3 Graph 3 5 4 6 Tree Graph Traversal: Problem: Search for a certain node or traverse all nodes in the graph Depth First Search Once a possible path is found, continue the search until the end of the path Breadth First Search Start several paths at a time, and advance in each one step at a time 10 Advanced Data Structures Introduction to Object Oriented Programming Object Oriented Programming: You've heard it a lot in the past several years. Everybody is saying it. What is all the fuss about objects and object-oriented technology? Is it real? Or is it hype? Well, the truth is--it's a little bit of both. Object-oriented technology does, in fact, provide many benefits to software developers and their products. However, historically a lot of hype has surrounded this technology, causing confusion in both managers and programmers alike. Many companies fell victim to this hardship (or took advantage of it) and claimed that their software products were object-oriented when, in fact, they weren't. These false claims confused consumers, causing widespread misinformation and mistrust of object-oriented technology. Object: As the name object-oriented implies, objects are key to understanding object-oriented technology. You can look around you now and see many examples of real-world objects: your dog, your desk, your television set, your bicycle. Definition: An object is a software bundle of variables and related methods Class: In the real world, you often have many objects of the same kind. For example, your bicycle is just one of many bicycles in the world. Using object-oriented terminology, we say that your 11 Advanced Data Structures bicycle object is an instance of the class of objects known as bicycles. Bicycles have some state (current gear, current cadence, two wheels) and behavior (change gears, brake) in common. However, each bicycle's state is independent of and can be different from other bicycles. Definition: A class is a blueprint or prototype that defines the variables and methods common to all objects of a certain kind. Inheritance: Acquiring the properties of one class in another class is called inheritance The Benefits of Inheritance Subclasses provide specialized behaviors from the basis of common elements provided by the super class. Through the use of inheritance, programmers can reuse the code in the superclass many times. Programmers can implement superclasses called abstract classes that define "generic" behaviors. The abstract superclass defines and may partially implement the behavior but much of the class is undefined and unimplemented. Other programmers fill in the details with specialized subclasses. Data Abstraction: The essential element of object oriented programming in abstraction. The complexity of programming in object oriented programming is maintained through abstraction. For example, the program consist of data and code which work over data. While executing a program we don’t thing in which location that data is being stored how the input device is transferring the input to the memory etc. this abstraction allows us to execute the program without thinking deeply about the complexity of execution of program. Encapsulation: Encapsulation is the mechanism that binds together code and the data and keeps them safe from outside world. In the sense it is a protective wrapper that prevents the code and data from being 12 Advanced Data Structures accessed by other code defied outside the wrapper. Access is controlled through a well defined interface. Polymorphism: Existing in more that one form is called polymorphism. Polymorphism means the ability to take more that one form. For example an operation may exhibit different behavior in different behavior in different instances. For example consider operation of addition. For two numbers the operation will generate a sum. If the operands are string the operation would produces a third string by concatenation. C++ supports polymorphism through method overloading and operator overloading Method overloading: if the same method name used for different procedures that the method is said to be overloaded. Dynamic Binding: Binding refer to the linking of a procedure call to the code to be executed in response to the call. Dynamic binding means that the code associated with a given procedure call is not know until the time of the call at runtime. It is associated with a polymorphism reference depends on the dynamic type of that reference. Message communication: An object oriented program consists of objects that communicate with each other. The process of programming in an object oriented language therefore involves the following basic steps: 1. creating classes that define objects and their behaviors. 2. creating objects from class definitions. 3. establishing communication among objects. 13 Advanced Data Structures Abstract Data Types: An Abstract Data Type (ADT) is more a way of looking at a data structure: focusing on what it does and ignoring how it does its job. A stack or a queue is an example of an ADT. It is important to understand that both stacks and queues can be implemented using an array. It is also possible to implement stacks and queues using a linked list. This demonstrates the "abstract" nature of stacks and queues: how they can be considered separately from their implementation. To best describe the term Abstract Data Type, it is best to break the term down into "data type" and then "abstract". Data type: When we consider a primitive type we are actually referring to two things: a data item with certain characteristics and the permissible operations on that data. An int in Java, for example, can contain any whole-number value from -2,147,483,648 to +2,147,483,647. It can also be used with the operators +, -, *, and /. The data type's permissible operations are an inseparable part of its identity; understanding the type means understanding what operations can be performed on it. In C++, any class represents a data type, in the sense that a class is made up of data (fields) and permissible operations on that data (methods). By extension, when a data storage structure like a stack or queue is represented by a class, it too can be referred to as a data type. A stack is different in many ways from an int, but they are both defined as a certain arrangement of data and a set of operations on that data. abstract Now lets look at the "abstract" portion of the phrase. The word abstract in our context stands for "considered apart from the detailed specifications or implementation". In C++, an Abstract Data Type is a class considered without regard to its implementation. It can be thought of as a "description" of the data in the class and a list of operations that can be carried out on that data and instructions on how to use these operations. What is excluded though, is the 14 Advanced Data Structures details of how the methods carry out their tasks. An end user (or class user), you should be told what methods to call, how to call them, and the results that should be expected, but not HOW they work. We can further extend the meaning of the ADT when applying it to data structures such as a stack and queue. In Java, as with any class, it means the data and the operations that can be performed on it. In this context, although, even the fundamentals of how the data is stored should be invisible to the user. Users not only should not know how the methods work, they should also not know what structures are being used to store the data. Consider for example the stack class. The end user knows that push() and pop() (amoung other similar methods) exist and how they work. The user doesn't and shouldn't have to know how push() and pop() work, or whether data is stored in an array, a linked list, or some other data structure like a tree. 15 Advanced Data Structures Stack ADT Algorithms Push(item) { If (stack is full) print “ stack over flow” else Increment top ; Stack [top]= item; } Pop() { If( stack is empty) print” stack under flow” else Decrement top } Display() { If ( stack is empty) print” no element to display” else for i= top to 0 step -1 Print satck[i]; } 16 Advanced Data Structures Stack ADT #include<iostream.h> #include<conio.h> #include<stdlib.h> class stack { int stk[5]; int top; public: stack() { top=-1; } void push(int x) { if(top > 4) { cout <<"stack over flow"; return; } stk[++top]=x; cout <<"inserted" <<x; } void pop() { if(top <0) { cout <<"stack under flow"; return; } cout <<"deleted" <<stk[top--]; } void display() { if(top<0) { cout <<" stack empty"; return; } 17 Advanced Data Structures for(int i=top;i>=0;i--) cout <<stk[i] <<" "; } }; void main() { int ch; stack st; clrscr(); while(1) { cout <<"\n1.push 2.pop 3.display 4.exit\nEnter ur choice"; cin >> ch; switch(ch) { case 1: cout <<"enter the element"; cin >> ch; st.push(ch); break; case 2: st.pop(); break; case 3: st.display();break; case 4: exit(0); } } } OUTPUTS 1.push 2.pop 3.display Enter ur choice2 stack under flow 1.push 2.pop 3.display Enter ur choice1 enter the element2 inserted2 1.push 2.pop 3.display Enter ur choice1 enter the element3 inserted3 1.push 2.pop 3.display Enter ur choice2 deleted3 1.push 2.pop 3.display Enter ur choice1 enter the element5 18 4.exit 4.exit 4.exit 4.exit 4.exit Advanced Data Structures Queue ADT Algorithms Insert ( item) { If rear = max -1 then print “ queue is full” else { Increment rear Queue [rear]=item; } } Delete() { If front = rear print “queue is empty” else Increment front } Display() { If front=rear print “queue is empty “ else For i =front to rear Print queue[i]; } 19 Advanced Data Structures Queue ADT #include<iostream.h> #include<conio.h> #include<stdlib.h> class queue { int queue[5]; int rear,front; public: queue() { rear=-1; front=-1; } void insert(int x) { if(rear > 4) { cout <<"queue over flow"; front=rear=-1; return; } queue[++rear]=x; cout <<"inserted" <<x; } void delet() { if(front==rear) { cout <<"queue under flow"; return; } cout <<"deleted" <<queue[++front]; } void display() { if(rear==front) { cout <<" queue empty"; 20 Advanced Data Structures return; } for(int i=front+1;i<=rear;i++) cout <<queue[i]<<" "; } }; void main() { int ch; queue qu; clrscr(); while(1){ cout <<"\n1.insert 2.delet 3.display 4.exit\nEnter ur choice"; cin >> ch; switch(ch) { case 1: cout <<"enter the element"; cin >> ch; qu.insert(ch); break; case 2: qu.delet(); break; case 3: qu.display();break; case 4: exit(0); } } } OUTPUT 1.insert 2.delet 3.display 4.exit Enter ur choice1 enter the element21 inserted21 1.insert 2.delet 3.display 4.exit Enter ur choice1 enter the element22 inserted22 1.insert 2.delet 3.display 4.exit Enter ur choice1 enter the element16 inserted16 1.insert 2.delet 3.display 4.exit Enter ur choice3 21 22 16 1.insert 2.delet 3.display 4.exit 21 Advanced Data Structures Algorithm for Stack Using Linked List Push(item) { If (stack is full) print “ stack over flow” else goto end of list and let it be temp temp->next=item item->next=NULL; } Pop() { If(head is null) print” stack under flow” else goto last but one node and let it be temp temp->next=NULL } Display() { If ( head=NULL) print” no element to display” else { Temp=head; While(temp!=NULL) { Print(“temp->data) Temp=temp->next; } } 22 Advanced Data Structures Stack Using Linked List #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: class node *next; int data; }; class stack : public node { node *head; int tos; public: stack() { os=-1; } void push(int x) { if (tos < 0 ) { head =new node; head->next=NULL; head->data=x; tos ++; } else { node *temp,*temp1; temp=head; if(tos >= 4) { cout <<"stack over flow"; return; } tos++; while(temp->next != NULL) temp=temp->next; temp1=new node; 23 Advanced Data Structures temp->next=temp1; temp1->next=NULL; temp1->data=x; } } void display() { node *temp; temp=head; if (tos < 0) { cout <<" stack under flow"; return; } while(temp != NULL) { cout <<temp->data<< " "; temp=temp->next; } } void pop() { node *temp; temp=head; if( tos < 0 ) { cout <<"stack under flow"; return; } tos--; while(temp->next->next!=NULL) { temp=temp->next; } temp->next=NULL; } }; void main() { stack s1; int ch; clrscr(); while(1) { 24 Advanced Data Structures cout <<"\n1.PUSH\n2.POP\n3.DISPLAY\n4.EXIT\n enter ru choice:"; cin >> ch; switch(ch) { case 1: cout <<"\n enter a element"; cin >> ch; s1.push(ch); break; case 2: s1.pop();break; case 3: s1.display(); break; case 4: exit(0); } } } OUTPUT 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:1 enter a element23 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:1 enter a element67 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:3 23 67 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:2 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:3 23 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:2 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:2 stack under flow 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:4 25 Advanced Data Structures Algorithm Queue using Linked List Insert ( item) { If rear = max -1 then print “ queue is full” else { Increment rear Create a new node called item goto last node in the list and let it be temp temp-next=item; item-next=NULL; } } Delete() { If front = rear print “queue is empty” else { Increment front head=head-next; } } Display() { If front=rear print “queue is empty “ else Temp=head; While(temp!=NULL) { Print(“temp-data) Temp=temp-next; } } 26 Advanced Data Structures Queue using Linked List #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: class node *next; int data; }; class queue : public node { node *head; int front,rare; public: queue() { front=-1; rare=-1; } void push(int x) { if (rare < 0 ) { head =new node; head->next=NULL; head->data=x; rare ++; } else { node *temp,*temp1; temp=head; if(rare >= 4) { cout <<"queue over flow"; return; } rare++; while(temp->next != NULL) temp=temp->next; 27 Advanced Data Structures temp1=new node; temp->next=temp1; temp1->next=NULL; temp1->data=x; } } void display() { node *temp; temp=head; if (rare < 0) { cout <<" queue under flow"; return; } while(temp != NULL) { cout <<temp->data<< " "; temp=temp->next; } } void pop() { node *temp; temp=head; if( rare < 0) { cout <<"queue under flow"; return; } if(front == rare) { front = rare =-1; head=NULL; return; } front++; head=head->next; } }; void main() { queue s1; 28 Advanced Data Structures int ch; clrscr(); while(1) { cout <<"\n1.PUSH\n2.POP\n3.DISPLAY\n4.EXIT\n enter ru choice:"; cin >> ch; switch(ch) { case 1: cout <<"\n enter a element"; cin >> ch; s1.push(ch); break; case 2: s1.pop();break; case 3: s1.display(); break; case 4: exit(0); } } } OUTPUT 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:1 enter a element23 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:1 enter a element54 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:3 23 54 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:2 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:2 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:2 queue under flow 1.PUSH 2.POP 3.DISPLAY 4.EXIT enter ru choice:4 29 Advanced Data Structures Algorithms fo DeQueue Using Double Linked List Algorithm Insertfirst(item) { if dequeue is empty { Item-next=item-prev=NULL; tail=head=item; } else if(dequeue is full) print” insertion is not possible” else { item-next=head; item-prev=NULL; head=item; } } Algorithm Insertlast (item) { if dequeue is empty { Item-next=item-prev=NULL; tail=head=item; } else if(dequeue is full) print” insertion is not possible” else { tail-next=head; item-prev=tail; tail=item; } } Deletefirst() { If (dequeue is empty) print” no node to delete”; else { Head=head-next; Head-prev=NULL; } } 30 Advanced Data Structures Deletelast() { if (dequeue is empty) print” no node to delete”; else { tail=tail-prev; tail-next=NULL; } } Displayfirst() { if( dequeue is empty) print “ no node to display” else { temp=head; while(temp-next!=null) then do { print(temp-data); temp=temp-next; } } } Displaylast() { if( dequeue is empty) print “ no node to display” else { temp=tail while(temp-prevt!=null) then do { print(temp-data); temp=temp-prev; } } } 31 Advanced Data Structures Implementation of DeQueue Using Double Linked List #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: int data; class node *next; class node *prev; }; class dqueue: public node { node *head,*tail; int top1,top2; public: dqueue() { top1=0; top2=0; head=NULL; tail=NULL; } void push(int x) { node *temp; int ch; if(top1+top2 >=5) { cout <<"dqueue overflow"; return ; } if( top1+top2 == 0) { head = new node; head->data=x; head->next=NULL; head->prev=NULL; tail=head; top1++; 32 Advanced Data Structures } else { cout <<" Add element 1.FIRST 2.LAST\n enter ur choice:"; cin >> ch; if(ch==1) { top1++; temp=new node; temp->data=x; temp->next=head; temp->prev=NULL; head->prev=temp; head=temp; } else { top2++; temp=new node; temp->data=x; temp->next=NULL; temp->prev=tail; tail->next=temp; tail=temp; } } } void pop() { int ch; cout <<"Delete 1.First Node 2.Last Node\n Enter ur choice:"; cin >>ch; if(top1 + top2 <=0) { cout <<"\nDqueue under flow"; return; } if(ch==1) { head=head->next; head->prev=NULL; top1--; } 33 Advanced Data Structures else { top2--; tail=tail->prev; tail->next=NULL; } } void display() { int ch; node *temp; cout <<"display from 1.Staring 2.Ending\n Enter ur choice"; cin >>ch; if(top1+top2 <=0) { cout <<"under flow"; return ; } if (ch==1) { temp=head; while(temp!=NULL) { cout << temp->data <<" "; temp=temp->next; } } else { temp=tail; while( temp!=NULL) { cout <<temp->data << " "; temp=temp->prev; } } } }; void main() { dqueue d1; int ch; clrscr(); 34 Advanced Data Structures while (1) { cout <<"1.INSERT 2.DELETE 3.DISPLAU 4.EXIT\n Enter ur choice:"; cin >>ch; switch(ch) { case 1: cout <<"enter element"; cin >> ch; d1.push(ch); break; case 2: d1.pop(); break; case 3: d1.display(); break; case 4: exit(1); } } } OUTPUT 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:1 enter element4 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:1 enter element5 Add element 1.FIRST 2.LAST enter ur choice:1 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:1 enter element6 Add element 1.FIRST 2.LAST enter ur choice:2 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:3 display from 1.Staring 2.Ending Enter ur choice1 5 4 6 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:2 Delete 1.First Node 2.Last Node Enter ur choice:1 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:3 display from 1.Staring 2.Ending Enter ur choice1 4 6 1.INSERT 2.DELETE 3.DISPLAU 4.EXIT Enter ur choice:4 35 Advanced Data Structures Algorithm for Circular Queue Algorithm Insertfirst(item) { if cqueue is empty then head=item; else if(cqueue is full) print” insertion is not possible” else { Rear=(rear +1) mod max } cqueue[rear]=x; } Algorithm Deletet() { If (dequeue is empty) print” no node to delete”; else { Front=(front+1) mod max } } Algorithm display() { If (front >rear) display elements for front to max and 0 to rear Else display elements from front to rear } 36 Advanced Data Structures Implementation of Circular Queue Using Array #include<iostream.h> #include<conio.h> #include<stdlib.h> class cqueue { int q[5],front,rare; public: cqueue() { front=-1; rare=-1; } void push(int x) { if(front ==-1 && rare == -1) { q[++rare]=x; front=rare; return; } else if(front == (rare+1)%5 ) { cout <<" Circular Queue over flow"; return; } rare= (rare+1)%5; q[rare]=x; } void pop() { if(front==-1 && rare== -1) { cout <<"under flow"; return; } else if( front== rare ) { front=rare=-1; return; 37 Advanced Data Structures } front= (front+1)%5; } void display() { int i; if( front <= rare) { for(i=front; i<=rare;i++) cout << q[i]<<" "; } else { for(i=front;i<=4;i++) { cout <<q[i] << " "; } for(i=0;i<=rare;i++) { cout << q[i]<< " "; } } } }; void main(){ int ch; cqueue q1; clrscr(); while( 1) { cout<<"\n1.INSERT 2.DELETE 3.DISPLAY cin >> ch; switch(ch) { case 1: cout<<"enter element"; cin >> ch; q1.push(ch); break; case 2: q1.pop(); break; case 3: q1.display(); break; case 4: exit(0); } } } 38 4.EXIT\nEnter ur choice"; Advanced Data Structures OUTPUT 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice1 enter element4 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice1 enter element5 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice1 enter element3 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice3 453 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice2 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice3 53 1.INSERT 2.DELETE 3.DISPLAY 4.EXIT Enter ur choice4 39 Advanced Data Structures Program to Algorithm Implementfor Functions Dictionary of a Dictionary #include<iostream.h> #include<conio.h> #include<stdlib.h> # define max 10 typedef struct list { int data; struct list *next; }node_type; node_type *ptr[max],*root[max],*temp[max]; class Dictionary { public: int index; Dictionary(); void insert(int); void search(int); void delete_ele(int); }; Dictionary::Dictionary() { index=-1; for(int i=0;i<max;i++) { root[i]=NULL; ptr[i]=NULL; temp[i]=NULL; } } void Dictionary::insert(int key) { index=int(key%max); ptr[index]=(node_type*)malloc(sizeof(node_type)); ptr[index]->data=key; if(root[index]==NULL) { 40 Advanced Data Structures root[index]=ptr[index]; root[index]->next=NULL; temp[index]=ptr[index]; } else { temp[index]=root[index]; while(temp[index]->next!=NULL) temp[index]=temp[index]->next; temp[index]->next=ptr[index]; } } void Dictionary::search(int key) { int flag=0; index=int(key%max); temp[index]=root[index]; while(temp[index]!=NULL) { if(temp[index]->data==key) { cout<<"\nSearch key is found!!"; flag=1; break; } else temp[index]=temp[index]->next; } if (flag==0) cout<<"\nsearch key not found......."; } void Dictionary::delete_ele(int key) { index=int(key%max); temp[index]=root[index]; while(temp[index]->data!=key && temp[index]!=NULL) { ptr[index]=temp[index]; temp[index]=temp[index]->next; } ptr[index]->next=temp[index]->next; cout<<"\n"<<temp[index]->data<<" has been deleted."; temp[index]->data=-1; 41 Advanced Data Structures temp[index]=NULL; free(temp[index]); } void main() { int val,ch,n,num; char c; Dictionary d; clrscr(); do { cout<<"\nMENU:\n1.Create"; cout<<"\n2.Search for a value\n3.Delete an value"; cout<<"\nEnter your choice:"; cin>>ch; switch(ch) { case 1: cout<<"\nEnter the number of elements to be inserted:"; cin>>n; cout<<"\nEnter the elements to be inserted:"; for(int i=0;i<n;i++) { cin>>num; d.insert(num); } break; case 2: cout<<"\nEnter the element to be searched:"; cin>>n; d.search(n); case 3: cout<<"\nEnter the element to be deleted:"; cin>>n; d.delete_ele(n); break; default: cout<<"\nInvalid choice...."; } cout<<"\nEnter y to continue......"; cin>>c; }while(c=='y'); getch(); } 42 Advanced Data Structures OUTPUT MENU: 1.Create 2.Search for a value 3.Delete an value Enter your choice:1 Enter the number of elements to be inserted:8 Enter the elements to be inserted:10 4 5 8 7 12 6 1 Enter y to continue......y MENU: 1.Create 2.Search for a value 3.Delete an value Enter your choice:2 Enter the element to be searched:12 Search key is found!! Enter the element to be deleted:1 1 has been deleted. Enter y to continue......y 43 Advanced Data Structures AVL TREE Algorithm insertion(int x) { If(tree is empty) then root is empty Otherwise { temp=search(item); // temp is the node where search for the item halts if( item > temp) then temp-right=item; otherwise temp-left =item Reconstruction procedure: rotating tree left rotation and right rotation Suppose that the rotation occurs at node x Left rotation: certain nodes from the right subtree of x move to its left subtree; the root of the right subtree of x becomes the new root of the reconstructed subtree Right rotation at x: certain nodes from the left subtree of x move to its right subtree; the root of the left subtree of x becomes the new root of the reconstructed subtree } Algorithm Search(int x) Algorithm delete() { Case 1: the node to be deleted Case 2: the node to be deleted is, its right subtree is empty Case 3: the node to be deleted is, its left subtree is empty Case 4: the node to be deleted right child } is a leaf has no right child, that has no left child, that has a left child and a Algorithm Search(x, root) { if(tree is empty ) then print” tree is empty” otherwise If(x grater than root) search(root-right); Otherwise if(x less than root ) search(root-left) Otherwise return true } } 44 Advanced Data Structures AVL TREE #include<iostream.h> #include<conio.h> #include<stdlib.h> #include<math.h> void insert(int,int ); void delte(int); void display(int); int search(int); int search1(int,int); int avltree[40],t=1,s,x,i; void main() { int ch,y; for(i=1;i<40;i++) avltree[i]=-1; while(1) { cout <<"1.INSERT\n2.DELETE\n3.DISPLAY\n4.SEARCH\n5.EXIT\nEnter your choice:"; cin >> ch; switch(ch) { case 1: cout <<"enter the element to insert"; cin >> ch; insert(1,ch); break; case 2: cout <<"enter the element to delete"; cin >>x; y=search(1); if(y!=-1) delte(y); else cout<<"no such element in avlavltree"; break; case 3: display(1); cout<<"\n"; for(int i=0;i<=32;i++) cout <<i; 45 Advanced Data Structures cout <<"\n"; break; case 4: cout <<"enter the element to search:"; cin >> x; y=search(1); if(y == -1) cout <<"no such element in avltree"; else cout <<x << "is in" <<y <<"position"; break; case 5: exit(0); } } } void insert(int s,int ch ) { int x,y; if(t==1) { avltree[t++]=ch; return; } x=search1(s,ch); if(avltree[x]>ch) { avltree[2*x]=ch; y=log(2*x)/log(2); if(height(1,y)) { if( x%2==0 ) update1(); else update2(); } } else { avltree[2*x+1]=ch; y=log(2*x)/log(2); if(height(1,y)) { if(x%2==1) update1(); else update2(); } 46 Advanced Data Structures } t++; } void delte(int x) { if( avltree[2*x]==-1 && avltree[2*x+1]==-1) avltree[x]=-1; else if(avltree[2*x]==-1) { avltree[x]=avltree[2*x+1]; avltree[2*x+1]=-1; } else if(avltree[2*x+1]==-1) { avltree[x]=avltree[2*x]; avltree[2*x]=-1; } else { avltree[x]=avltree[2*x]; delte(2*x); } t--; } int search(int s) { if(t==1) { cout <<"no element in avltree"; return -1; } if(avltree[s]==-1) return avltree[s]; if(avltree[s]>x) search(2*s); else if(avltree[s]<x) search(2*s+1); else return s; } void display(int s) { if(t==1) { cout <<"no element in avltree:"; 47 Advanced Data Structures return; } for(int i=1;i<40;i++) if(avltree[i]==-1) cout <<" "; else cout <<avltree[i]; return ; } int search1(int s,int ch) { if(t==1) { cout <<"no element in avltree"; return -1; } if(avltree[s]==-1) return s/2; if(avltree[s] > ch) search1(2*s,ch); else search1(2*s+1,ch); } int height(int s,int y) { if(avltree[s]==-1) return; } 48 Advanced Data Structures OUTPUT 1.insert 2.display 3.delete 4.search 5.exit Enter u r choice to perform on AVL tree1 Enter an element to insert into tree4 do u want to continuey 1.insert 2.display 3.delete 4.search 5.exit Enter u r choice to perform on AVL tree1 Enter an element to insert into tree5 do u want to continuey 1.insert 2.display 3.delete 4.search 5.exit Enter u r choice to perform on AVL tree3 Enter an item to deletion5 itemfound do u want to continuey 1.insert 2.display 3.delete 4.search 5.exit Enter u r choice to perform on AVL tree2 4 do u want to continue4 49 Advanced Data Structures Breath First Search Algorithm Algorithm BFS(s): Input: A vertex s in a graph Output: A labeling of the edges as “discovery” edges and “cross edges” initialize container L0 to contain vertex s i 0 while Li is not empty do create container Li+1 to initially be empty for each vertex v in Li do if edge e incident on v do let w be the other endpoint of e if vertex w is unexplored then label e as a discovery edge insert w into Li+1 else label e as a cross edge i i + 1 50 Advanced Data Structures Breath First Search Implementation #include<iostream.h> #include<conio.h> #include<stdlib.h> int cost[10][10],i,j,k,n,qu[10],front,rare,v,visit[10],visited[10]; void main() { clrscr(); int m; cout <<"enterno of vertices"; cin >> n; cout <<"ente no of edges"; cin >> m; cout <<"\nEDGES \n"; for(k=1;k<=m;k++) { cin >>i>>j; cost[i][j]=1; } cout <<"enter initial vertex"; cin >>v; cout <<"Visitied vertices\n"; cout << v; xvisited[v]=1; k=1; while(k<n) { for(j=1;j<=n;j++) if(cost[v][j]!=0 && visited[j]!=1 && visit[j]!=1) { visit[j]=1; qu[rare++]=j; } v=qu[front++]; cout<<v << " "; k++; visit[v]=0; visited[v]=1; } } 51 Advanced Data Structures OUTPUT enterno of vertices9 ente no of edges9 EDGES 12 23 15 14 47 78 89 26 57 enter initial vertex1 Visited vertices 12 4 5 3 6 7 8 9 52 Advanced Data Structures Depth First Search Algorithm Algorithm DFS(v); Input: A vertex v in a graph Output: A labeling of the edges as “discovery” edges and “backedges” for each edge e incident on v do if edge e is unexplored then let w be the other endpoint of e if vertex w is unexplored then label e as a discovery edge recursively call DFS(w) else label e as a backedge 53 Advanced Data Structures Depth First Search #include<iostream.h> #include<conio.h> #include<stdlib.h> int cost[10][10],i,j,k,n,stk[10],top,v,visit[10],visited[10]; void main() { int m; clrscr(); cout <<"enterno of vertices"; cin >> n; cout <<"ente no of edges"; cin >> m; cout <<"\nEDGES \n"; for(k=1;k<=m;k++) { cin >>i>>j; cost[i][j]=1; } cout <<"enter initial vertex"; cin >>v; cout <<"ORDER OF VISITED VERTICES"; cout << v <<" "; visited[v]=1; k=1; while(k<n) { for(j=n;j>=1;j--) if(cost[v][j]!=0 && visited[j]!=1 && visit[j]!=1) { visit[j]=1; stk[top]=j; top++; } v=stk[--top]; cout<<v << " "; k++; visit[v]=0; visited[v]=1; } } 54 Advanced Data Structures OUTPUT enterno of vertices9 ente no of edges9 EDGES 12 23 26 15 14 47 57 78 89 enter initial vertex1 ORDER OF VISITED VERTICES1 2 3 6 4 7 8 9 5 55 Advanced Data Structures Prim’s Algorithm Algorithm Prim(E,Cost,n,t) { Let (k, l) be an edge of minimum cost in E; Mincost= cost[k,l]; t[1,1]=k; t[1,2]=l; for i=1 to n do { If (cost[i, l]<cost[k,l]) then near[i]=l; Else Near[i]=k; Near[k]=near[j]=0; } For i=2 to n -1 do { Let j be an index such that nearpj]!= 0 and cost[j,near[j]] is minimum T[I,1]=j ; t[I,2]=near[j] mincost=mincost + cost[j,near[j]]; near[j]=0; for k=1 to n do if(near[k] !=0 ) and cost[k,near[k]]) then near[j]=k } } 56 >cost[k,j]) Advanced Data Structures Prim’s Algorithm #include<iostream.h> #include<conio.h> #include<stdlib.h> int cost[10][10],i,j,k,n,stk[10],top,v,visit[10],visited[10],u; void main() { int m,c; clrscr(); cout <<"enterno of vertices"; cin >> n; cout <<"ente no of edges"; cin >> m; cout <<"\nEDGES Cost\n"; for(k=1;k<=m;k++) { cin >>i>>j>>c; cost[i][j]=c; } for(i=1;i<=n;i++) for(j=1;j<=n;j++) if(cost[i][j]==0) cost[i][j]=31999; cout <<"ORDER OF VISITED VERTICES"; k=1; while(k<n) { m=31999; if(k==1) { for(i=1;i<=n;i++) for(j=1;j<=m;j++) if(cost[i][j]<m) { m=cost[i][j]; u=i; } } else { for(j=n;j>=1;j--) 57 Advanced Data Structures if(cost[v][j]<m && visited[j]!=1 && visit[j]!=1) { visit[j]=1; stk[top]=j; top++; m=cost[v][j]; u=j; } } cost[v][u]=31999; v=u; cout<<v << " "; k++; visit[v]=0; visited[v]=1; } } OUTPUT enterno of vertices7 ente no of edges9 EDGES Cost 1 6 10 6 5 25 5 4 22 4 3 12 3 2 16 2 7 14 5 7 24 4 7 18 1 2 28 ORDER OF VISITED VERTICES1 6 5 4 3 2 58 Advanced Data Structures Kruskal’s Algorithm Algorithm Krushkal(E, cost,n,t) { for i=1 to n do parent[i]=-1; i=0; mincost=0; while( I < n-1) { Delete a minimum coast edge (u,v) form the heap and reheapfy using adjust J=find(u); K=find(v); If(j!=k) then { i=i+1; t[I,1]=u; t[I,2]=v; mincost=mincost+ cost[u,v]; union(j,k) } If( i != n-1) the write (“ no spanning tree”); else Return mincost } } 59 Advanced Data Structures Kruskal’s Algorithm #include<iostream.h> #include<conio.h> #include<stdlib.h> int cost[10][10],i,j,k,n,m,c,visit,visited[10],l,v,count,count1,vst,p; main() { int dup1,dup2; cout<<"enter no of vertices"; cin >> n; cout <<"enter no of edges"; cin >>m; cout <<"EDGE Cost"; for(k=1;k<=m;k++) { cin >>i >>j >>c; cost[i][j]=c; cost[j][i]=c; } for(i=1;i<=n;i++) for(j=1;j<=n;j++) if(cost[i][j]==0) cost[i][j]=31999; visit=1; while(visit<n) { v=31999; for(i=1;i<=n;i++) for(j=1;j<=n;j++) if(cost[i][j]!=31999 && cost[i][j]<v && cost[i][j]!=-1 ) { count =0; for(p=1;p<=n;p++) { if(visited[p]==i || visited[p]==j) count++; } if(count >= 2) { for(p=1;p<=n;p++) if(cost[i][p]!=31999 && p!=j) dup1=p; 60 Advanced Data Structures for(p=1;p<=n;p++) if(cost[j][p]!=31999 && p!=i) dup2=p; if(cost[dup1][dup2]==-1) continue; } l=i; k=j; v=cost[i][j]; } cout <<"edge from " <<l <<"-->"<<k; cost[l][k]=-1; cost[k][l]=-1; visit++; count=0; count1 =0; for(i=1;i<=n;i++) { if(visited[i]==l) count++; if(visited[i]==k) count1++; } if(count==0) visited[++vst]=l; if(count1==0) visited[++vst]=k; } } 61 Advanced Data Structures Single Source Shortest Path #include<iostream.h> #include<conio.h> #include<stdio.h> int shortest(int ,int); int cost[10][10],dist[20],i,j,n,k,m,S[20],v,totcost,path[20],p; void main() { int c; clrscr(); cout <<"enter no of vertices"; cin >> n; cout <<"enter no of edges"; cin >>m; cout <<"\nenter\nEDGE Cost\n"; for(k=1;k<=m;k++) { cin >> i >> j >>c; cost[i][j]=c; } for(i=1;i<=n;i++) for(j=1;j<=n;j++) if(cost[i][j]==0) cost[i][j]=31999; cout <<"enter initial vertex"; cin >>v; cout << v<<"\n"; shortest(v,n); } shortest(int v,int n) { int min; for(i=1;i<=n;i++) { S[i]=0; dist[i]=cost[v][i]; } path[++p]=v; 62 Advanced Data Structures S[v]=1; dist[v]=0; for(i=2;i<=n-1;i++) { k=-1; min=31999; for(j=1;j<=n;j++) { if(dist[j]<min && S[j]!=1) { min=dist[j]; k=j; } } if(cost[v][k]<=dist[k]) p=1; path[++p]=k; for(j=1;j<=p;j++) cout<<path[j]; cout <<"\n"; //cout <<k; S[k]=1; for(j=1;j<=n;j++) if(cost[k][j]!=31999 && dist[j]>=dist[k]+cost[k][j] && S[j]!=1) dist[j]=dist[k]+cost[k][j]; } } OUTPUT enter no of vertices6 enter no of edges11 enter EDGE Cost 1 2 50 1 3 45 1 4 10 2 3 10 2 4 15 3 5 30 63 Advanced Data Structures 4 1 10 4 5 15 5 2 20 5 3 35 653 enter initial vertex1 1 14 145 1452 13 64 Advanced Data Structures Non recursive Pre order Traversing Algorithm Algorithm preorder( root) { 1. current = root; //start the traversal at the root node 2. while(current is not NULL or stack is nonempty) if(current is not NULL) { visit current; push current onto stack; current = current->llink; } else { pop stack into current; current = current->rlink; //prepare to visit //the right subtree } 65 Advanced Data Structures Non recursive Pre order Traversing #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: class node *left; class node *right; int data; }; class tree: public node { public: int stk[50],top; node *root; tree() { root=NULL; top=0; } void insert(int ch) { node *temp,*temp1; if(root== NULL) { root=new node; root->data=ch; root->left=NULL; root->right=NULL; return; } temp1=new node; temp1->data=ch; temp1->right=temp1->left=NULL; temp=search(root,ch); if(temp->data>ch) temp->left=temp1; else temp->right=temp1; 66 Advanced Data Structures } node *search(node *temp,int ch) { if(root== NULL) { cout <<"no node present"; return NULL; } if(temp->left==NULL && temp->right== NULL) return temp; if(temp->data>ch) { if(temp->left==NULL) return temp; search(temp->left,ch);} else { if(temp->right==NULL) return temp; search(temp->right,ch); } } void display(node *temp) { if(temp==NULL) return ; display(temp->left); cout<<temp->data <<" "; display(temp->right); } void preorder( node *root) { node *p,*q; p=root; q=NULL; top=0; while(p!=NULL) { cout <<p->data << " "; if(p->right!=NULL) { stk[top]=p->right->data; top++; } p=p->left; if(p==NULL && top>0) 67 Advanced Data Structures { p=pop(root); } } } node * pop(node *p) { int ch; ch=stk[top-1]; if(p->data==ch) { top--; return p; } if(p->data>ch) pop(p->left); else pop(p->right); } }; void main() { tree t1; int ch,n,i; while(1) { cout <<"\n1.INSERT\n2.DISPLAY 3.PREORDER TRAVERSE\n4.EXIT\nEnter your choice:"; cin >> ch; switch(ch) { case 1: cout <<"enter no of elements to insert:"; cout<<"\n enter the elements"; cin >> n; for(i=1;i<=n;i++) { cin >> ch; t1.insert(ch); } break; case 2: t1.display(t1.root);break; case 3: t1.preorder(t1.root); break; case 4: exit(1); } } } 68 Advanced Data Structures OUTPUT 1.INSERT 2.DISPLAY 3.PREORDER TRAVERSE 4.EXIT Enter your choice:1 enter no of elements to insert enter the elements7 5 24 36 11 44 2 21 1.INSERT 2.DISPLAY 3.PREORDER TRAVERSE 4.EXIT Enter your choice:2 2 5 11 21 24 36 44 1.INSERT 2.DISPLAY 3.PREORDER TRAVERSE 4.EXIT Enter your choice:3 5 2 24 11 21 36 44 1.INSERT 2.DISPLAY 3.PREORDER TRAVERSE 4.EXIT Enter your choice:4 69 Advanced Data Structures Non recursive In order Traversing Algorithm inorder( root) { 1. current = root; //start traversing the binary tree at // the root node 2. while(current is not NULL or stack is nonempty) if(current is not NULL) { push current onto stack; current = current->llink; } else { pop stack into current; visit current; //visit the node current = current->rlink; //move to the //right child } } 70 Advanced Data Structures Non recursive In order Traversing #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: class node *left; class node *right; int data; }; class tree: public node { public: int stk[50],top; node *root; tree() { root=NULL; top=0; } void insert(int ch) { node *temp,*temp1; if(root== NULL) { root=new node; root->data=ch; root->left=NULL; root->right=NULL; return; } temp1=new node; temp1->data=ch; temp1->right=temp1->left=NULL; temp=search(root,ch); if(temp->data>ch) temp->left=temp1; else temp->right=temp1; 71 Advanced Data Structures } node *search(node *temp,int ch) { if(root== NULL) { cout <<"no node present"; return NULL; } if(temp->left==NULL && temp->right== NULL) return temp; if(temp->data>ch) { if(temp->left==NULL) return temp; search(temp->left,ch);} else { if(temp->right==NULL) return temp; search(temp->right,ch); } } void display(node *temp) { if(temp==NULL) return ; display(temp->left); cout<<temp->data; display(temp->right); } void inorder( node *root) { node *p; p=root; top=0; do { while(p!=NULL) { stk[top]=p->data; top++; p=p->left; } if(top>0) { p=pop(root); 72 Advanced Data Structures cout << p->data; p=p->right; } }while(top!=0 || p!=NULL); } node * pop(node *p) { int ch; ch=stk[top-1]; if(p->data==ch) { top--; return p; } if(p->data>ch) pop(p->left); else pop(p->right); } }; void main() { tree t1; int ch,n,i; while(1) { cout <<"\n1.INSERT\n2.DISPLAY 3.INORDER TRAVERSE\n4.EXIT\nEnter your choice:"; cin >> ch; switch(ch) { case 1: cout <<"enter no of elements to insert:"; cin >> n; for(i=1;i<=n;i++) { cin >> ch; t1.insert(ch); } break; case 2: t1.display(t1.root);break; case 3: t1.inorder(t1.root); break; case 4: exit(1); } } 73 Advanced Data Structures } OUTPUT 1.INSERT 2.DISPLAY 3.INORDER TRAVERSE 4.EXIT Enter your choice:1 enter no of elements to inser 5 24 36 11 44 2 21 1.INSERT 2.DISPLAY 3.INORDER TRAVERSE 4.EXIT Enter your choice:3 251121243644 1.INSERT 2.DISPLAY 3.INORDER TRAVERSE 4.EXIT Enter your choice:3 251121243644 1.INSERT 2.DISPLAY 3.INORDER TRAVERSE 4.EXIT Enter your choice:4 74 Advanced Data Structures Non recursive Post order Traversing Algorithm Algorithm postorder( node root) { 1. current = root; //start traversal at root node 2. v = 0; 3. if(current is NULL) the binary tree is empty 4. if(current is not NULL) a. push current into stack; b. push 1 onto stack; c. current = current->llink; d. while(stack is not empty) if(current is not NULL and v is 0) { push current and 1 onto stack; current = current->llink; } else { pop stack into current and v; if(v == 1) { push current and 2 onto stack; current = current->rlink; v = 0; } else visit current; }} 75 Advanced Data Structures Non recursive Post order Traversing #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: class node *left; class node *right; int data; }; class tree: public node { public: int stk[50],top; node *root; tree() { root=NULL; top=0; } void insert(int ch) { node *temp,*temp1; if(root== NULL) { root=new node; root->data=ch; root->left=NULL; root->right=NULL; return; } temp1=new node; temp1->data=ch; temp1->right=temp1->left=NULL; temp=search(root,ch); if(temp->data>ch) temp->left=temp1; else temp->right=temp1; 76 Advanced Data Structures } node *search(node *temp,int ch) { if(root== NULL) { cout <<"no node present"; return NULL; } if(temp->left==NULL && temp->right== NULL) return temp; if(temp->data>ch) { if(temp->left==NULL) return temp; search(temp->left,ch);} else { if(temp->right==NULL) return temp; search(temp->right,ch); } } void display(node *temp) { if(temp==NULL) return ; display(temp->left); cout<<temp->data << " "; display(temp->right); } void postorder( node *root) { node *p; p=root; top=0; while(1) { while(p!=NULL) { stk[top]=p->data; top++; if(p->right!=NULL) stk[top++]=-p->right->data; p=p->left; } 77 Advanced Data Structures } while(stk[top-1] > 0 || top==0) { if(top==0) return; cout << stk[top-1] <<" "; p=pop(root); } if(stk[top-1]<0) { stk[top-1]=-stk[top-1]; p=pop(root); } } node * pop(node *p) { int ch; ch=stk[top-1]; if(p->data==ch) { top--; return p; } if(p->data>ch) pop(p->left); else pop(p->right); } }; void main() { tree t1; int ch,n,i; clrscr(); while(1) { cout <<"\n1.INSERT\n2.DISPLAY 3.POSTORDER TRAVERSE\n4.EXIT\nEnter your choice:"; cin >> ch; switch(ch) { case 1: cout <<"enter no of elements to insert:"; cout<<"\n enter the elements"; cin >> n; for(i=1;i<=n;i++) { cin >> ch; t1.insert(ch); 78 Advanced Data Structures } break; case 2: t1.display(t1.root);break; case 3: t1.postorder(t1.root); break; case 4: exit(1); } } } OUTPUT 1.INSERT 2.DISPLAY 3.POSTORDER TRAVERSE 4.EXIT Enter your choice:1 enter no of elements to insert: enter the elements7 5 24 36 11 44 2 21 1.INSERT 2.DISPLAY 3.POSTORDER TRAVERSE 4.EXIT Enter your choice:2 2 5 11 21 24 36 44 1.INSERT 2.DISPLAY 3.POSTORDER TRAVERSE 4.EXIT Enter your choice:3 2 21 11 44 36 24 5 1.INSERT 2.DISPLAY 3.POSTORDER TRAVERSE 4.EXIT Enter your choice:4 79 Advanced Data Structures Quick Sort Algorithm Algorithm quicksort(a[],p,q) { V=a[p]; i=p; j=q; if(i<j) { repeat { repeat I=i+1; Until( a[i]> v); Repeat J=j-1; Until(a[j]<v); If(i<j) then interchange ( a[i],a[j]) }until (i<=j); interchange(a[j], a[p]) } quicksort(a[],p,j); quicksort(a[],j+1,q); } 80 Advanced Data Structures Quick Sort #include<iostream.h> #include<conio.h> int a[10],l,u,i,j; void quick(int *,int,int); void main() { clrscr(); cout <<"enter 10 elements"; for(i=0;i<10;i++) cin >> a[i]; l=0; u=9; quick(a,l,u); cout <<"sorted elements"; for(i=0;i<10;i++) cout << a[i] << " "; getch(); } void quick(int a[],int l,int u) { int p,temp; if(l<u) { p=a[l]; i=l; j=u; while(i<j) { while(a[i] <= p && i<j ) i++; while(a[j]>p && i<=j ) j--; if(i<=j) { temp=a[i]; a[i]=a[j]; a[j]=temp;} } temp=a[j]; a[j]=a[l]; 81 Advanced Data Structures a[l]=temp; cout <<"\n"; for(i=0;i<10;i++) cout <<a[i]<<" "; quick(a,l,j-1); quick(a,j+1,u); } } OUTPUT enter 10 elements5 2 3 16 25 1 20 7 8 61 14 1 2 3 5 25 16 20 7 8 61 1 2 3 5 25 16 20 7 8 61 1 2 3 5 25 16 20 7 8 61 1 2 3 5 25 16 20 7 8 61 1 2 3 5 25 16 20 7 8 61 1 2 3 5 8 16 20 7 25 61 1 2 3 5 7 8 20 16 25 61 1 2 3 5 7 8 16 20 25 61 1 2 3 5 7 8 16 20 25 61 sorted elements1 2 3 5 7 8 16 20 25 61 82 Advanced Data Structures Merge Sort Algorithm Algorithm Mergesort(low,high) { If(low<high) { Mid=(low+high)/2; Mergesort(low,mid); Mergesort(mid+1,high) Merge(low,mid,high); } } Algorithm Merge(low,mid,high) { h=low; i=low; j=mid+1; While(h<=mid and j<=high) do { If(a[h]<a[j]) then { b[i]=a[h]; h=h+1; } else { b[i]=a[j]; J=j+1; } if(h>mid) { For k= j to high do b[i]=a[k]; i=i+1; } Else { For k=h to mid do b[i]=a[k]; i=i+1; } For k= low to high do a[k]=b[k]; } } 83 Advanced Data Structures Merge Sort #include<iostream.h> #include<conio.h> void mergesort(int *,int,int); void merge(int *,int,int,int); int a[20],i,n,b[20]; void main() { clrscr(); cout <<"\N enter no of elements"; cin >> n; cout <<"enter the elements"; for(i=0;i<n;i++) cin >> a[i]; mergesort(a,0,n-1); cout <<" numbers after sort"; for(i=0;i<n;i++) cout << a[i] << " "; getch(); } void mergesort(int a[],int i,int j) { int mid; if(i<j) { mid=(i+j)/2; mergesort(a,i,mid); mergesort(a,mid+1,j); merge(a,i,mid,j); } } void merge(int a[],int low,int mid ,int high) { int h,i,j,k; h=low; i=low; j=mid+1; 84 Advanced Data Structures while(h<=mid && j<=high) { if(a[h]<=a[j]) b[i]=a[h++]; else b[i]=a[j++]; i++; } if( h > mid) for(k=j;k<=high;k++) b[i++]=a[k]; else for(k=h;k<=mid;k++) b[i++]=a[k]; cout <<"\n"; for(k=low;k<=high;k++) { a[k]=b[k]; cout << a[k] <<" "; } } OUTPUT N enter no of elements8 12 5 61 60 50 1 70 81 enter the elements 5 12 60 61 5 12 60 61 1 50 70 81 1 50 70 81 1 5 12 50 60 61 70 81 numbers after sort1 5 12 50 60 61 70 81 85 Advanced Data Structures Heap Sort Algorithm Definition: A heap is a list in which each element contains a key, such that the key in the element at position k in the list is at least as large as the key in the element at position 2k + 1 (if it exists), and 2k + 2 (if it exists) Algorithm Heapify(a[],n) { For i=n/2 to 1 step -1 Adjustify (a,i,n); } Algorithm Adjustify(a[],i,n) { Repeat { J=leftchild(i) Compare left and right child of a[i] and store the index of grater number in j Compare a[j] and a[i] If (a[j]>a[i]) then Copy a[j] to a[i] and move to next level }until(j<n) } 86 Advanced Data Structures Heap Sort #include<stdio.h> #include<conio.h> int a[20],n; main() { int i,j,temp; clrscr(); printf("ente n"); scanf("%d",&n); printf("enter the elements"); for(i=1;i<=n;i++) scanf("%d",&a[i]); heapify(a,n); for(j=1;j<=n;j++) printf("%d",a[j]); for(i=n;i>=2;i--) { temp=a[i]; a[i]=a[1]; a[1]=temp; adjust(a,1,i-1); printf("\n"); for(j=1;j<=n;j++) printf("%d ",a[j]); } printf("\nelements after sort"); for(i=1;i<=n;i++) printf("%d ",a[i]); } heapify(int a[],int n) { int i; for( i=n/2;i>=1;i--) adjust(a,i,n); } 87 Advanced Data Structures adjust(int a[],int i,int n) { int j,iteam; j=2*i; iteam=a[i]; while(j<=n) { if(j<n && a[j]<a[j+1]) j=j+1; if(iteam>=a[j]) break; a[j/2]=a[j]; j=2*j; } a[j/2]=iteam; } 88 Advanced Data Structures All Paris Shortest Path #include<iostream.h> #include<conio.h> int min(int a,int b); int cost[10][10],a[10][10],i,j,k,c; void main() { int n,m; cout <<"enter no of vertices"; cin >> n; cout <<"enter no od edges"; cin >> m; cout<<"enter the\nEDGE Cost\n"; for(k=1;k<=m;k++) { cin>>i>>j>>c; a[i][j]=cost[i][j]=c; } for(i=1;i<=n;i++) for(j=1;j<=n;j++) { if(a[i][j]== 0 && i !=j) a[i][j]=31999; } for(k=1;k<=n;k++) for(i=1;i<=n;i++) for(j=1;j<=n;j++) a[i][j]=min(a[i][j],a[i][k]+a[k][j]); cout <<"Resultant adj matrix\n"; for(i=1;i<=n;i++) { for( j=1;j<=n;j++) { if(a[i][j] !=31999) cout << a[i][j] <<" "; } cout <<"\n"; } 89 Advanced Data Structures getch(); } int min(int a,int b) { if(a<b) return a; else return b; } OUTPUT enter no of vertices3 enter no od edges5 enter the EDGE Cost 124 216 1 3 11 313 232 Resultant adj matrix 046 502 370 90 Advanced Data Structures Algorithms for Binary Search Tree Algorithm Insert(item) { If(tree is empty) then root is empty Otherwise { temp=search(item); // temp is the node where search for the item halts if( item > temp) then temp-right=item; otherwise temp-left =item } } Algorithm Search(x, root) { if(tree is empty ) then print” tree is empty” otherwise If(x grater than root) search(root-right); Otherwise if(x less than root ) search(root-left) Otherwise return true } } Algorithm Delete(x) { Search for x in the tree If (not found) print” not found” Otherwise{ If ( x has no child) delete x; If(x has left child) move the left child to x position If(x has right child) move the right child to x position If(x has both left and right children) replace ‘x’ with greatest of left subtree of ‘x ‘ or smallest of right subtree of ‘x’ and delete selected node in the subtree } } 91 Advanced Data Structures Binary Search Tree #include<iostream.h> #include<conio.h> #include<stdlib.h> class node { public: class node *left; class node *right; int data; }; class tree: public node { public: int stk[50],top; node *root; tree() { root=NULL; top=0; } void insert(int ch) { node *temp,*temp1; if(root== NULL) { root=new node; root->data=ch; root->left=NULL; root->right=NULL; return; } temp1=new node; temp1->data=ch; temp1->right=temp1->left=NULL; temp=search(root,ch); if(temp->data>ch) temp->left=temp1; else temp->right=temp1; 92 Advanced Data Structures } node *search(node *temp,int ch) { if(root== NULL) { cout <<"no node present"; return NULL; } if(temp->left==NULL && temp->right== NULL) return temp; if(temp->data>ch) { if(temp->left==NULL) return temp; search(temp->left,ch);} else { if(temp->right==NULL) return temp; search(temp->right,ch); } } void display(node *temp) { if(temp==NULL) return ; display(temp->left); cout<<temp->data << " "; display(temp->right); } node * pop(node *p) { int ch; ch=stk[top-1]; if(p->data==ch) { top--; return p; } if(p->data>ch) pop(p->left); else pop(p->right); } }; 93 Advanced Data Structures void main() { tree t1; int ch,n,i; clrscr(); while(1) { cout <<"\n1.INSERT\n2.POP\n3.DISPLAY\n4.EXIT\nEnter your choice:"; cin >> ch; switch(ch) { case 1: cout <<"enter no of elements to insert:"; cout<<"\n enter the elements"; cin >> n; for(i=1;i<=n;i++) { cin >> ch; t1.insert(ch); } break; case 2: t1.pop(); break; case 3: t1.display(t1.root);break; case 4: exit(1); } } } 1.INSERT 2.POP 3.DISPLAY 4.EXIT Enter your choice:1 enter no of elements to insert: enter the elements7 5 24 36 11 44 2 21 1.INSERT 2.POP 3.DISPLAY 4.EXIT Enter your choice:3 2 5 11 21 24 36 44 1.INSERT 2.POP 3.DISPLAY 4.EXIT Enter your choice2 2 11 21 24 36 44 1.INSERT 2.POP 3.DISPLAY 4.EXIT 4.EXITEnter your choice:4 94 Advanced Data Structures Optimal Binary Search Tree #include<iostream.h> #include<conio.h> #include<stdio.h> #define MAX 10 int find(int i,int j); void print(int,int); int p[MAX],q[MAX],w[10][10],c[10][10],r[10][10],i,j,k,n,m; char idnt[7][10]; void main() { clrscr(); cout << "enter the no, of identifiers"; cin >>n; cout <<"enter identifiers"; for(i=1;i<=n;i++) gets(idnt[i]); cout <<"enter success propability for identifiers"; for(i=1;i<=n;i++) cin >>p[i]; cout << "enter failure propability for identifiers"; for(i=0;i<=n;i++) cin >> q[i]; for(i=0;i<=n;i++) { w[i][i]=q[i]; c[i][i]=r[i][i]=0; w[i][i+1]=q[i]+q[i+1]+p[i+1]; r[i][i+1]=i+1; c[i][i+1]=q[i]+q[i+1]+p[i+1]; } w[n][n]=q[n]; r[n][n]=c[n][n]=0; for(m=2;m<=n;m++) { for(i=0;i<=n-m;i++) { j=i+m; w[i][j]=w[i][j-1]+p[j]+q[j]; k=find(i,j); r[i][j]=k; 95 Advanced Data Structures c[i][j]=w[i][j]+c[i][k-1]+c[k][j]; } } cout <<"\n"; print(0,n); } int find(int i,int j) { int min=2000,m,l; for(m=i+1;m<=j;m++) if(c[i][m-1]+c[m][j]<min) { min=c[i][m-1]+c[m][j]; l=m; } return l; } void print(int i,int j) { if(i<j) puts(idnt[r[i][j]]); else return; print(i,r[i][j]-1); print(r[i][j],j); } OUTPUT enter the no, of identifiers4 enter identifiersdo if int while enter success propability for identifiers3 3 1 1 enter failure propability for identifiers2 3 1 1 1 tree in preorder form if do int while 96 Advanced Data Structures Viva Voice Questions 1. What is the difference between an ARRAY and a LIST? 2. What is faster : access the element in an ARRAY or in a LIST? 3. Define a constructor - what it is and how it might be called (2 methods). 4. Describe PRIVATE, PROTECTED and PUBLIC - the differences and give examples. 5. What is a COPY CONSTRUCTOR and when is it called (this is a frequent question !)? 6. Explain term POLIMORPHISM and give an example using eg. SHAPE object: If I have a base class SHAPE, how would I define DRAW methods for two objects CIRCLE and SQUARE. 7. What is the word you will use when defining a function in base class to allow this function to be a polimorphic function? 8. You have two pairs: new() and delete() and another pair : alloc() and free(). Explain differences between eg. new() and malloc() 9. Difference between “C structure” and “C++ structure”. 10. Diffrence between a “assignment operator” and a “copy constructor” 11. What is the difference between “overloading” and “overridding”? 12. Explain the need for “Virtual Destructor”. 13. Can we have “Virtual Constructors”? 14. What are the different types of polymorphism? 15. What are Virtual Functions? How to implement virtual functions in “C” 16. What are the different types of Storage classes? 17. What is Namespace? 97 Advanced Data Structures 18. Difference between “vector” and “array”? 19. How to write a program such that it will delete itself after exectution? 20. Can we generate a C++ source code from the binary file? 21. What are inline functions? 22. What is “strstream” ? 23. Explain “passing by value”, “passing by pointer” and “passing by reference” 24. Have you heard of “mutable” keyword? 25. Is there something that I can do in C and not in C++? 26. What is the difference between “calloc” and “malloc”? 27. What will happen if I allocate memory using “new” and free it using “free” or allocate sing “calloc” and free it using “delete”? 28. When shall I use Multiple Inheritance? 29. How to write Multithreaded applications using C++? 30. Write any small program that will compile in “C” but not in “C++” 31. What is Memory Alignment? 32. what is the difference between a tree and a graph? 33. How to insert an element in a binary search tree? 34. How to delete an element from a binary search tree? 35. How to search an element in a binary search tree? 36. what is the disadvantage in binary search tree? 37. what is ment by height balanced tree? 38. Give examples for height blanced tree? 39. What is a 2-3 tree? 98 Advanced Data Structures 40. what is a dictonary? 41.What is a binary search tree? 42. what is an AVL tree? 43. how height balancing is performed in AVL tree? 44. what is a Red Black tree? 45. what is difference between linked list and an array? 46. how dynamic memory allocation is performed in c++? 47. what are tree traversing techniques? 48. what are graph traversing techniques? 49. what is the technique in quick sort.? 50 what is the technique in merge sort? 51. what is data structure. 52. how to implement two stacks in an array? 53. what is ment by generic programming? 54. write the syntax for function templet? 55. write the syntax for class templet? 56. what is ment by stream? 57. what is the base class for all the streams? 58. how to create a file in c++? 59. how do you read a file in c++? 60. how do you write a file in c++? 99