#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll mod = 1e9+7, dp[1<<21+5];
int main()
{
    int n, a;
    cin >> n;
    int arr[n][n];
    for(int i = 0; i < n; i++)for(int j = 0; j < n; j++)cin >> arr[i][j];
    dp[0]++;
    for(int i = 0; i < (1 << n)-1; i++){
        int a = __builtin_popcount(i);
        for(int j = 0; j < n; j++){
            if((i&(1<<j)) == 0 and arr[a][j] == 1 )dp[i|((1<<j))] = (dp[i|((1<<j))]+ dp[i])%mod;
        }
    }
    cout << dp[(1<<n)-1];
}
### Prompt

Your task is to create a Cpp solution to the following problem:

There are N men and N women, both numbered 1, 2, \ldots, N.

For each i, j (1 \leq i, j \leq N), the compatibility of Man i and Woman j is given as an integer a_{i, j}. If a_{i, j} = 1, Man i and Woman j are compatible; if a_{i, j} = 0, they are not.

Taro is trying to make N pairs, each consisting of a man and a woman who are compatible. Here, each man and each woman must belong to exactly one pair.

Find the number of ways in which Taro can make N pairs, modulo 10^9 + 7.

Constraints

* All values in input are integers.
* 1 \leq N \leq 21
* a_{i, j} is 0 or 1.

Input

Input is given from Standard Input in the following format:


N
a_{1, 1} \ldots a_{1, N}
:
a_{N, 1} \ldots a_{N, N}


Output

Print the number of ways in which Taro can make N pairs, modulo 10^9 + 7.

Examples

Input

3
0 1 1
1 0 1
1 1 1


Output

3


Input

4
0 1 0 0
0 0 0 1
1 0 0 0
0 0 1 0


Output

1


Input

1
0


Output

0


Input

21
0 0 0 0 0 0 0 1 1 0 1 1 1 1 0 0 0 1 0 0 1
1 1 1 0 0 1 0 0 0 1 0 0 0 0 1 1 1 0 1 1 0
0 0 1 1 1 1 0 1 1 0 0 1 0 0 1 1 0 0 0 1 1
0 1 1 0 1 1 0 1 0 1 0 0 1 0 0 0 0 0 1 1 0
1 1 0 0 1 0 1 0 0 1 1 1 1 0 0 0 0 0 0 0 0
0 1 1 0 1 1 1 0 1 1 1 0 0 0 1 1 1 1 0 0 1
0 1 0 0 0 1 0 1 0 0 0 1 1 1 0 0 1 1 0 1 0
0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 1 1 1 1 1 1
0 0 1 0 0 1 0 0 1 0 1 1 0 0 1 0 1 0 1 1 1
0 0 0 0 1 1 0 0 1 1 1 0 0 0 0 1 1 0 0 0 1
0 1 1 0 1 1 0 0 1 1 0 0 0 1 1 1 1 0 1 1 0
0 0 1 0 0 1 1 1 1 0 1 1 0 1 1 1 0 0 0 0 1
0 1 1 0 0 1 1 1 1 0 0 0 1 0 1 1 0 1 0 1 1
1 1 1 1 1 0 0 0 0 1 0 0 1 1 0 1 1 1 0 0 1
0 0 0 1 1 0 1 1 1 1 0 0 0 0 0 0 1 1 1 1 1
1 0 1 1 0 1 0 1 0 0 1 0 0 1 1 0 1 0 1 1 0
0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 1 1 0 0 1
0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 0 0 1 1 0 1
0 0 0 0 1 1 1 0 1 0 1 1 1 0 1 1 0 0 1 1 0
1 1 0 1 1 0 0 1 1 0 1 1 0 1 1 1 1 1 0 1 0
1 0 0 1 1 0 1 1 1 1 1 0 1 0 1 1 0 0 0 0 0


Output

102515160

### Response

```cpp
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll mod = 1e9+7, dp[1<<21+5];
int main()
{
    int n, a;
    cin >> n;
    int arr[n][n];
    for(int i = 0; i < n; i++)for(int j = 0; j < n; j++)cin >> arr[i][j];
    dp[0]++;
    for(int i = 0; i < (1 << n)-1; i++){
        int a = __builtin_popcount(i);
        for(int j = 0; j < n; j++){
            if((i&(1<<j)) == 0 and arr[a][j] == 1 )dp[i|((1<<j))] = (dp[i|((1<<j))]+ dp[i])%mod;
        }
    }
    cout << dp[(1<<n)-1];
}
```