POJ1222_EXTENDED LIGHTS OUT

#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;

int a[7][8],ans[7];
int T,n,m,cas=0,c[8];
int f[8];
bool findans;

bool check(int cur)
{
    int tmp=ans[cur];
    for (int i=1; i<=6; i++) f[i]=tmp&1,tmp>>=1;
    for (int i=1; i<=6; i++){
        tmp=(ans[cur-1]&c[i])==(ans[cur+1]&c[i])?1:0;
        tmp^=a[cur][i]^f[i-1]^f[i]^f[i+1];
        if (!tmp) return false;
    }
    return true;
}

void dfs(int cur)
{
    if (cur==5){
        if (check(cur)) findans=true;
        return;
    }
    for (int i=0; i<c[7]; i++){
        ans[cur+1]=i;
        if (cur>0 && !check(cur)) continue;
        dfs(cur+1);
        if (findans) return;
    }
}

int main()
{
    c[1]=1;
    for (int i=2; i<=7; i++) c[i]=c[i-1]+c[i-1];
    scanf("%d",&T);
    while (T--)
    {
        findans=false;
        for (int i=1; i<=5; i++)
            for (int j=1; j<=6; j++) scanf("%d",&a[i][j]);
        dfs(0);
        printf("PUZZLE #%d\n",++cas);
        for (int i=1; i<=5; i++){
            printf("%d",ans[i]&1);
            for (int j=2; j<=6; j++) printf(" %d",(ans[i]&c[j])?1:0);
            printf("\n");
        }
    }
    return 0;
}