Binary Search Trees II
Morse Code
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An Application: Morse Code Table
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Let's create a BST to translate ASCII
characters into Morse Code symbols.
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Use genBST1.h template.
Will create a new class to be the template
parameter.
New empty C++ project
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ASCII_to_Morse_Code
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Initial main.cpp
#include <iostream>
using namespace std;
int main()
{
cout << "Enter an ASCII string to be translated into Morse Code\n";
char buffer[1000];
cin.getline(buffer, 1000);
cout << "You entered:\n";
cout << buffer;
cin.get();
cin.get();
return 0;
}
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Initial Program Running
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Class Morse_Code_Pair
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Add class Morse_Code_Pair
Each object will specify the Morse Code
symbol for one ASCII character.
We will build a BST of these objects.
Use the BST to translate ASCII into
Morse Code.
Copy source files from:
http://www.cse.usf.edu/~turnerr/Data_Structures/Downloads/
2011_03_07_Morse_Code_BST/
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Morse_Code_Pair.h
#pragma once
#include <iostream>
#include <string>
class Morse_Code_Pair
{
public:
std::string symbol;
char value;
// A Morse code symbol.
// The letter or digit represented
// by this symbol
public:
// Default constructor
Morse_Code_Pair();
// Normal constructor
Morse_Code_Pair(std::string symbol_, char value_);
// Accessor functions
std::string get_symbol() const {return symbol; }
char get_value() const {return value; }
};
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Morse_Code_Pair.h
// Less than operator
bool operator<(const Morse_Code_Pair& lhs,
const Morse_Code_Pair& rhs);
// Equals operator
bool operator==(const Morse_Code_Pair& lhs,
const Morse_Code_Pair& rhs);
// Output operator
std::ostream& operator<<(std::ostream& out,
const Morse_Code_Pair& s);
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Morse_Code_Pair.cpp
#include "Morse_Code_Pair.h"
using namespace std;
// Default constructor
Morse_Code_Pair::Morse_Code_Pair() : symbol("", ' ')
{}
// Normal constructor
Morse_Code_Pair::Morse_Code_Pair(string symbol_, char value_) :
symbol(symbol_), value(value_)
{}
// Less then operator
bool operator< (const Morse_Code_Pair& lhs,
const Morse_Code_Pair& rhs)
{
char c_lhs = lhs.get_value();
char c_rhs = rhs.get_value();
return c_lhs < c_rhs;
}
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Morse_Code_Pair.cpp
// Equals operator
bool operator==(const Morse_Code_Pair& lhs,
const Morse_Code_Pair& rhs)
{
char c_lhs = lhs.get_value();
char c_rhs = rhs.get_value();
return c_lhs == c_rhs;
}
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Morse_Code_Pair.cpp
ostream& operator<<(ostream& out,
const Morse_Code_Pair& s)
{
string symbol_string = s.get_symbol();
for (size_t i = 0; i < symbol_string.length(); ++i)
{
if (symbol_string[i] == '_')
{
symbol_string[i] = '-';
}
}
out << s.get_value() << " " << symbol_string;
return out;
}
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main.cpp
#include <iostream>
#include "genBST1.h"
#include "Morse_Code_Pair.h"
using namespace std;
// Conservative upper bound on length of a single Morse code symbol
const int MAX_SYMBOL_LEN = 10;
// Binary Search Tree to map Morse code symbols to characters
BST<Morse_Code_Pair> morse_map;
void add_symbol_to_map(string symbol, char value)
{
Morse_Code_Pair sym(symbol, value);
morse_map.insert(sym);
}
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build_map
In main.cpp:
void build_map()
{
add_symbol_to_map("....", 'H');
add_symbol_to_map("___..", '8');
add_symbol_to_map("._.", 'R');
add_symbol_to_map("...__", '3');
add_symbol_to_map("_._.", 'C');
add_symbol_to_map("__", 'M');
add_symbol_to_map("..._", 'V');
add_symbol_to_map(".____", '1');
add_symbol_to_map(".....", '5');
add_symbol_to_map("._", 'A');
add_symbol_to_map(".", 'E');
add_symbol_to_map(".___", 'J');
add_symbol_to_map("___", 'O');
add_symbol_to_map("_", 'T');
add_symbol_to_map("_.._", 'X');
add_symbol_to_map(".__", 'W');
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build_map
add_symbol_to_map("_____", '0');
add_symbol_to_map("..___", '2');
add_symbol_to_map("...._", '4');
add_symbol_to_map("_....", '6');
add_symbol_to_map("____.", '9');
add_symbol_to_map("_...", 'B');
add_symbol_to_map("_..", 'D');
add_symbol_to_map(".._.", 'F');
add_symbol_to_map("..", 'I');
add_symbol_to_map("_._", 'K');
add_symbol_to_map(".__.", 'P');
add_symbol_to_map("_.__", 'Y');
add_symbol_to_map("__...", '7');
add_symbol_to_map("__.", 'G');
add_symbol_to_map("._..", 'L');
add_symbol_to_map("_.", 'N');
add_symbol_to_map("__._", 'Q');
add_symbol_to_map("...", 'S');
add_symbol_to_map(".._", 'U');
add_symbol_to_map("__..", 'Z');
}
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main.cpp
int main()
{
build_map();
morse_map.display(cout);
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The Morse_Pair BST
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main.cpp
Add at end of main.cpp:
cout << "\n\nHere is the string in Morse Code:\n";
for (int i = 0; i < (int) strlen(buffer); ++i)
{
char c = toupper(buffer[i]);
Morse_Code_Pair* search_target = new Morse_Code_Pair("", c);
Morse_Code_Pair* mcp = morse_map.search(*search_target);
if (mcp == 0)
{
cout << " ";
}
else
{
string next_symbol = mcp->get_symbol();
cout << next_symbol << " ";
}
}
cout << endl;
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Program in Action
End of Presentation
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