Homework 12
• Due
Sun., 11/24
( MT sections )
Mon., 11/25
( WTh sections )
• Problems (2 of them)
http://www.cs.hmc.edu/courses/2002/fall/cs5/week_12/homework.html
• Tutors available
Saturday afternoons
Lac Lab
Sunday afternoons
Lac Lab
Sunday evenings
Lac Lab and AC
Monday evenings
Lac Lab and AC
M. Beaumont-Gay & M. Yi in LAC
E. Flynn, Y.M. Kim, & A. Klose in AC
M. Yi, C. Wottawa, & A. Utter in LAC
A. Kangas, P. Scott, A. Pipkin in AC
Problem 2 / Final Project
A “film database” application: 5 classes
class name
data member
data member type
Self-referential data ?
A film database application:
class Director
String fname
FilmDB filmDB
String lname
class Film
String title
int year
String rating
double review
Director dir
FilmDB
filmDB
// method skeletons…
class Film
{
// data members
Director
dir
class FilmDB
int count
Film[] films
class Director
{
private String fname;
private String lname;
private FilmDB filmDB;
// method skeletons
class FilmDB
{
// data members
Film[]
films
films[0]
films[1]
// method skeletons
Problem 2 - skeleton code
Classes
Data Members
CS5App
none
Film
String title
int year
String rating
double review
Director dir
Methods
public static void main(String[] args)
public static void printMenu()
public Film(String title, int year, String rating,
double review, Director dir)
public String getTitle()
public int getYear()
public String getRating()
public double getReview()
public void display()
Classes
Director
DirectorDB
FilmDB
Data Members
Methods
String fname
String lname
FilmDB filmDB
public Director(String fname, String lname,
int capacity)
public String getFullName()
public FilmDB getFilmDB()
int count
Director[] dirs
public DirectorDB(int capacity)
public void displayAllDirectors()
public void displayFilmsByDirector(String fname,
String lname)
public Director findDirectorByName(String fname,
String lname)
public void addDirector(Director dir)
public int getCount()
public boolean isFull()
int count
Film[] Films
public
public
public
public
public
public
public
public
public
public
FilmDB(int capacity)
boolean isFull()
int getCount()
void addFilm(Film f)
Film findFilmByTitle(String title)
void displayAllFilms()
void displayFilmsByTitle(String titlepiece)
void displayFilmsByYear(int year)
void displayFilmsByRating(String rating)
void displayFilmsByReview(double minreview)
Problem 2
• Implement the main menu (in the CS5App class)
Please choose an action from the following list:
0
1
2
3
4
5
6
Display
Display
Display
Display
Display
Display
Display
All Directors
All Films
Films by Title
Films by Director
Films by Year
Films by Rating (G, PG, …)
Films by Review (0 to 10)
7 Add a New Film
9 Quit
• Create skeleton versions of the necessary classes...
Care to Swap ?
Suppose we want to swap the variables x and y …
int x = 42;
int y = 5;
int x
int y
Problem 1 - recursion
void sort(double[] arr, int L, int H)
80
L
97
42
75
23
H
Iterative vs. Recursive
void moveMinToLeft(double[] arr, int L, int H)
80
L
97
42
75
23
H
Iterative vs. Recursive
void moveMinToLeft(double[] arr, int L, int H)
80
L
97
42
75
23
H
Swapping
Suppose we want to swap the H-1st and the Hth values...
80
L
97
42
75
23
H-1
H
Problem 1 - recursion
void sort(double[] arr, int L, int H)
80
L
97
42
75
23
H
Problem 1 - recursion
public static double harmonic(int N)
Problem 1 - recursion
public static String reverse(int N)
public static int chooseMove3Ply(Board b, char ox)
for (int m=0 ; m<b.getCols() ; ++m)
{
if (b.allowsMove(m))
{
Board b2 = b.newAddMove(m,ox);
if ( b2.winsFor(ox) || b2.isFull() )
score = evaluate(b,ox);
else
{
int m2 = chooseMove2Ply(b2,opp(ox));
Board b3 = b2.newAddMove(m2,opp(ox));
if ( b3.winsFor(opp(ox)) || b3.isFull() )
score = evaluate(b,ox);
else
{
int m3 = chooseMove1Ply(b3,ox);
Board b4 = b3.newAddMove(m3, ox);
score = evaluate(b4, ox);
}
}
if (score > BSSF)
{
BSSF = score;
BMSF = m;
}
}
}
// end if (b.allowsMove(m))
// end for (int m=0 ; …
return BMSF;
Ex. Cr.
evaluating move m
by finding score
remembering the best score
and the best move m so far
Looking N Ply ahead!
1-ply search
2-ply search
3-ply search
N-ply search
chooseMove1Ply chooseMove2Ply chooseMove3Ply
evaluate
1 - ply
2 - ply
(N-1) - ply
...
int chooseMove(Board b, char ox, int ply)
With a 4-ply lookahead, X will think every
move looks equivalent on this board
With a 5-ply lookahead, X will
know to move to column 3
0
1
2
3
4
5
6
‘X’
‘O’