JS1k: The JavaScript code golfing competition

var c=[[],[],[],[],[],[],[]],d=1,e=0,h=document.body,i="<tr>"+Array(8).join("<td style=height:25px;width:25px;background:#FFF>"),j=[];for(var k=0;k<7;k++)j[k]="<td align=center>"+(k+1);h.innerHTML="<table style=background:#FF0>"+Array(7).join(i)+"<tr>"+j.join("");var l=h.firstChild,m,p;function q(a,f){for(var b=0;b<4;b++){var g=b-3;for(var n=0;g<=b;g++){var r=p+f*g,o=c[m+a*g];n+=o&&o[r]}if(Math.abs(n)==4)return 1}}
document.documentElement.onkeypress=function(a){a=a.charCode-49;if(a>=0&&a<7){var f=c[a],b=f.length;if(b<7){f[b]=d;++e;p=b;m=a;l.rows[5-p].cells[m].style.background=d==1?"#A00":"#000";if(e==42)alert("Draw");else if(q(0,1)||q(1,0)||q(1,1)||q(1,-1))d>0?alert("Red won"):alert("Black won");d*=-1}}};

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