topical media & game development
game-javascript-math-ucla-chomp.htm / htm
<html><head><title>Chomp</title>
<script language="JavaScript">
var blank = "blank.gif";
var brown = "brown.jpeg";
var poison = "poison.jpeg";
var c=7; //c = # columns. Require 6 <= c <= 10.
var x,y;
var
ppos=[1,12,23,34,45,56,113,122,224,235,246,336,355,1114,1125,1133,1222,2226,2255,2335];
//perfect play for c=7 is achieved by adding
//67,257,347,477,2237,2357,2447,3377,3457,4557 to ppos.
//but ppos must be arranged in increasing order.
//For c=8, add 78,268,448,2248,2368,2458,2588,3338.
var n = [];
var box = [];
for (var i=1;i<=4;i++) {
box[i]=[];
}
function yourChoice(u,v) {
if (box[u][v]==1) {
Move(u,v);
encode();
if (n[1]+n[2]==1) {
alert("Good work!\n You won!");
return;
}
x=findMove();
Move(x,y+1);
if (box[1][2]+box[2][1]==0) alert("Nice try,\n but I won!");
}
}
function Move(x,y) {
for (var k1=x;k1<=4;k1++) {
for (var k2=y;k2<=c;k2++) {
document.images[(4-k1)*c+k2-1].src=blank;
box[k1][k2]=0;
}
}
}
function encode() { //maps position into n[1],n[2],n[3],n[4]
for (var i=1;i<5;i++) {
n[i]=0;
for (var j=1;j<=c;j++) {
n[i]=n[i]+box[i][j];
}
}
n[1]=n[1]+1;
}
function findMove() {
var t=10
var k=ppos.length-1;
for (y=n[1]-1;y>=n[2];y--) {
val=y+t*(n[2]+t*(n[3]+t*n[4]));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 1};
}
for (y=n[2]-1;y>=n[3];y--) {
val=n[1]+t*(y+t*(n[3]+t*n[4]));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 2};
val=y+t*(y+t*(n[3]+t*n[4]));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 1};
}
for (y=n[3]-1;y>=n[4];y--) {
val=n[1]+t*(n[2]+t*(y+t*n[4]));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 3};
val=n[1]+t*(y+t*(y+t*n[4]));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 2};
val=y+t*(y+t*(y+t*n[4]));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 1};
}
for (y=n[4]-1;y>=0;y--) {
val=n[1]+t*(n[2]+t*(n[3]+t*y));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 4};
val=n[1]+t*(n[2]+t*(y+t*y));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 3};
val=n[1]+t*(y+t*(y+t*y));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 2};
val=y+t*(y+t*(y+t*y));
while (val<ppos[k]) k--;
if (val==ppos[k]) {return 1};
}
if ((Math.random()>.4) && (n[4]>0)) {
y=n[4]-1;
return 4;
} else if ((Math.random()>.5) && (n[3]>0)) {
y=n[3]-1;
return 3;
} else if ((Math.random()>.67) && (n[2]>0)) {
y=n[2]-1;
return 2;
} else {
y=n[1]-1;
return 1;
}
}
function playAgain() {
for (var i=4;i>0;i--) {
for (var j=1;j<=c;j++) {
document.images[c*(i-1)+j-1].src= brown;
box[i][j]=1
}
}
document.images[c*3].src= poison;
box[1][1]=0;
}
</script><script charset="utf-8" id="injection_graph_func" src="game-javascript-math-ucla-injection_graph_func.js"></script></head><body>
<center>
<hr size="5">
<h1>CHOMP!</h1>
<i>JavaScript</i>
<hr size="5">
The game of Chomp is like Russian Roulette for chocolate lovers.<br>A move
consists of chomping a square out of the chocolate bar<br>along with any
squares to the right and above.<br>Players alternate moves.<p>
The lower left square is poisoned though and the player forced to chomp
it loses.</p><p>
Try your luck against the machine.<br>You chomp on a square by clicking on
the square with the mouse.<br>You move first. You can win from the initial
position, but be careful!
<script language="JavaScript">
document.write("<form name=game><table border=1 cellpadding=0 cellspacing=0><tr>");
for (var i=4;i>0;i--) {
for (var j=1;j<=c;j++) {
document.write('<td><a href="javascript:yourChoice('+i+','+j+')">'
+'<img src="brown.jpeg" border=0 height=40 width=40></a></td>');
}
document.write("</tr><tr>");
}
document.write("</tr></table>");
document.write("<input type=button value='New Game' onClick='playAgain();'>");
document.write("</form><p>");
playAgain();
</script></p><form name="game"><table border="1" cellpadding="0" cellspacing="0"><tbody><tr><td><a href="javascript:yourChoice(4,1)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(4,2)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(4,3)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(4,4)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(4,5)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(4,6)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(4,7)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td></tr><tr><td><a href="javascript:yourChoice(3,1)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(3,2)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(3,3)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(3,4)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(3,5)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(3,6)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(3,7)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td></tr><tr><td><a href="javascript:yourChoice(2,1)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(2,2)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(2,3)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(2,4)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(2,5)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(2,6)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(2,7)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td></tr><tr><td><a href="javascript:yourChoice(1,1)"><img src="game-javascript-math-ucla-poison.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(1,2)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(1,3)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(1,4)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(1,5)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(1,6)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td><td><a href="javascript:yourChoice(1,7)"><img src="game-javascript-math-ucla-brown.jpg" border="0" height="40" width="40"></a></td></tr><tr></tr></tbody></table><input value="New Game" onclick="playAgain();" type="button"></form><p>
</p></center></body></html>
(C) Æliens
20/2/2008
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