func_code_string: #include <bits/stdc++.h>   using namespace std;   int p[2][252], f[252][252], C[252], mod = 1e9 + 7, inv[252];   int qp(int a, int x) {     int i = 1;     for (; x; x >>= 1, a = 1ll * a * a % mod)       if (x & 1) i = 1ll * i * a % mod;     return i;   }   int main() {     int n, m, i, j, k, a;     scanf( %d%d , &n, &m);     for (inv[1] = 1, i = 2; i <= n; i++)       inv[i] = mod - 1ll * mod / i * inv[mod % i] % mod;     for (i = C[0] = p[0][0] = p[1][0] = 1; i <= n; i++) {       C[i] = 1ll * C[i - 1] * (n - i + 1) % mod * inv[i] % mod;       p[0][i] = 1ll * p[0][i - 1] * m % mod;       p[1][i] = 1ll * p[1][i - 1] * (m - 1) % mod;     }     for (i = k = 0, j = 1; i <= n; i++, j *= -1) {       a = 1ll * p[0][n - i] * p[1][i] % mod - p[1][n];       if (a < 0) a += mod;       if (a >= mod) a -= mod;       k += 1ll * j * C[i] * qp(a, n) % mod;       if (k < 0) k += mod;       if (k >= mod) k -= mod;     }     printf( %d , k);     return 0;   }   