#include #include #include #include using namespace std; int n; int mat[21][21]; long long dp[1 << 20]; long long rec(int red, int bitmask) { if(__builtin_popcount(bitmask) == n) { return 1; } if(dp[bitmask] != -1) { return dp[bitmask]; } long long result = 0; for(int i = 0; i < n; i++) { if(mat[red][i] == 1) { if((bitmask & (1 << i)) == 0) { int new_mask = (bitmask | (1 << i)); result += rec(red + 1, new_mask); } } } return dp[bitmask] = result; } int main() { ios_base::sync_with_stdio(0); int t; cin >> t; while(t--) { cin >> n; for(int i = 0; i < n; i++){ for(int j =0 ; j < n; j++) { cin >> mat[i][j]; } } memset(dp, -1, sizeof dp); cout << rec(0, 0) << endl; } return 0; }