#include using namespace std; using Int = long long; //INSERT ABOVE HERE const Int N = 4; Int a[N][N],z[N][N]; void check(){ for(Int i=0;i=N||nj<0||nj>=N) continue; Int x=a[ni][nj]; if((b>>x)&1) continue; Int nb=b|(1<>a[i][j]; for(Int i=0;i