lkarch.org/tools/mathisfun/www.mathsisfun.com/games/chess/chess_6k.js

M=I=P=N=q=K=J=Btime=0
Bt=1999
Al=-Bt
Ds=[10,-10]
BE=120
Rh=[]
G=[]
R=[]
KL=[3,3]
j=[0,1,5,3,3,9,63,0]
MV=[0,0,[1,10],[21,19,12,8],[11,9],[1,10,11,9],[1,10,11,9],0]
for(z=0;z<8;){j[z+8]=j[z]<<=4
m=MV[z++]
if(m){s=m.length
for(x=0;x<s;){m[s+x]=-m[x++]}}}
x='g00000000g'
y='gggggggggg'
b=y+y+"g23456432gg11111111g"+x+x+x+x+"g99999999ggABCDECBAg"+y+y
w=x+x+x+"000111100000123321000123553210"
a='000012346900'
Y=[]
PY=[]
bY=[]
for(y=0;y<12;y++){for(x=0;x<10;x++){z=(y*10)+x
PY[z]=parseInt(a.charAt(y))
bY[z]=parseInt(w.charAt((z<60)?z:119-z),35)&7
R[z]=parseInt(b.charAt(z),35)}}R[BE]=0
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r[s]=0
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d=(s+e)>>1
r[g]=0
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if(N){if(c){L.sort(cp)
c--
var i=L[0],j=i[1],k=i[2],t
b=-Z(c,V,i[0],j,k,-B,-A,i[3])[0]
for(z=1;z<N;z++){if(b>A)A=b
n=L[z]
t=-Z(c,V,n[0],n[1],n[2],-A-1,-A,n[3])[0]
if((t>A)&&(t<B))t=-Z(c,V,n[0],n[1],n[2],-B,-t,n[3])[0]
if(t>b){b=t
j=n[1]
k=n[2]
if(t>A)A=t
if(b>B){break}}}}else{b=Al
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r[d]=0}r[s]=S
r[e]=E
G[V].length--
return[b,j,k]}
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R[s]=0
H()
U=Z(c,U,0,BE,BE,Al,Bt,K)
R[s]=S
R[e]=E
return U[0]}
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if(M==P){H()
p=Pz(M,K,0)
for(;z<p.length;z++){t=t||(s==p[z][1]&&e==p[z][2])}
if(!t)return 0
if(Sf(0,8-M,s,e,K)>400)return 0}if(Sf(0,M,s,e,K)>400)c=1
var x=s%10,g=e-s,D=Ds[u],t=e%10,n=1+(N>>1),l="abcdefgh"
Df((M?'     ':(n<10?" ":"")+n+".  ")+l.charAt(x-1)+((s-x)/10-1)+(E?'x':'-')+l.charAt(t-1)+((e-t)/10-1)+(c?'+':' '))
if(Sf(1,8-M,s,e,K)<-400)fy(c)
if((E&7)==6){fy(1);return 0;}Rh[N]=[R.toString(),KL.toString(),K]
K=0
if(a==1){if(R[e+D]>15)R[s]+=4-b
if(g==2*D&&(R[e-1]&1||R[e+1]&1))K=s+D
if(!E&&g%10)Sh(e,e-D)}if(s==21+u*70||s==28+u*70)KL[u]&=(x<5)+1
if(e==21+u*70||e==28+u*70)KL[!u]&=(x<5)+1
if(a==6){if(g*g==4)Sh(s-4+(s<e)*7,s+g/2)
KL[u]=0}Sh(s,e)
H()
N++
M=8-M
return 1}
function fy(c){Df(c?'checkmate!':'stalemate!')
J=c++}
function H(){var z=99,Q
s0=(N<32)?4-(N>>3):(N>64)
G[0]=[]
G[8]=[]
kY=[]
pY=[[],[]]
for(;z>20;z--){a=R[z]
if(a&7)G[a&8][G[a&8].length]=[a,z]
Y[z]=bY[z]*s0
kY[z]=(N>40)||(10-2*bY[z])*s0
Q=pY[1][119-z]=pY[0][z]=PY[z]
if(N<7&&z>40){pY[0][z]=pY[1][119-z]=Q+(Math.random()*Y[z])|1
Y[24]=Y[94]=29}}}
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for(z=0;z<f;z++){W=e[z][1]
a=B[W]
if(e[z][0]==a){a&=7
if(a>1){c=a==6
H=c?kY:Y
T=b-H[W]
n=MV[a]
if(a==3||c){for(v=0;v<8;){X=W+n[v++]
E=B[X]
if(!E||(E&24)==V){w[++k]=[T+J[E]+H[X],W,X]}}if(c&&d){if(d&1&&!(B[W-1]+B[W-2]+B[W-3])&&CH(W-2,V,D,-1))w[++k]=[T+11,W,W-2]
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for(v=0;v<g;){E=0
m=n[v++]
X=W
while(!E){X+=m
E=B[X]
if(!E||(E&24)==V){w[++k]=[T+J[E]+H[X],W,X]}}}}}else{T=b-p[W]
X=W+D
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if(!p[W]&&(!B[X+D])){w[++k]=[T+p[X+D],W,X+D,X]}}if(K&&(K==X+1||K==X-1))w[++k]=[T+p[X],W,K]
for(h=X-1;h<X+2;h+=2){E=B[h]+U
if(E&7&&E&8){w[++k]=[T+J[E]+p[h],W,h]}}}}}return w}
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for(;W<S;W++){for(m=D-2;++m<a;){E=B[W+m]
if(E&&(E&8)==V&&((E&8)==1||(E&7)==6))return 0
E=0
X=W
while(!E){X+=m
E=B[X]
if((E==V+2+(m!=D)*2)||E==V+5)return 0}}for(z=0;z<8;)if(B[W+k[z++]]-V==3)return 0}E=0
W-=3
while(!E){W-=T
E=B[W]
if(E==V+2||E==V+5)return 0}return 1}
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O(q,I,1)
I=0
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q=Q
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mv(t[1],t[2],0)}}}}
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R[e]=a
R[s]=0
O(s,0,1)
O(e,a,1)}
function Df(x){d.FF.b.value+='\n '+x}
function Rf(a){P=a
for(var z=0;z<BE;z++)if(R[z]<16)O(z,R[z],1)
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mv(Tt[1],Tt[2],0)}}
function Gb(){if(!N)return
N-=2
var b=Rh[N]
R=eval("["+b[0]+"]")
KL=eval("["+b[1]+"]")
Df(' --undo--')
K=b[2]
M=N%2
Rf(M)
H()}
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Ic.left=(e.clientX+1)+'px'
Ic.top=(e.clientY-4)+'px'}
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d.images[x].src=y+'.gif'}
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for(y=90;y>10;y-=10){h+="<tr>"
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