func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 2e6 + 7;   const int M = 2e6 + 7;   const int lim = 1e6;   const int mod = 1e9 + 7;   const int inf = 0x3f3f3f3f;   long long ksm(long long a, long long b, long long p) {     long long ret = 1;     while (b) {       if (b & 1) (ret *= a) %= p;       (a *= a) %= p;       b >>= 1;     }     return ret;   }   long long inv(long long x) { return ksm(x, mod - 2, mod); }   int main() {     long long k, x, a = 1, b = 1, f1 = 0, f2 = 0;     scanf( %lld , &k);     for (int i = 1; i <= k; i++) {       scanf( %lld , &x);       if (x % 2 == 0) f1 = 1;       if (x == 0) f2 = 1;       (b *= x % (mod - 1)) %= mod - 1;       (a *= x % 2) %= 2;     }     b = (b - 1 + mod - 1) % (mod - 1);     long long bb = ksm(2, b, mod);     if (f1 == 0) f1 = -1;     long long aa = (bb + f1 + mod) % mod, t = ksm(2, (a - 1 + 2) % 2, 3);     t = (t + f1 + 3) % 3;     if (t == 0)       aa = aa * inv(3) % mod;     else       bb *= 3;     printf( %lld/%lld n , aa, bb);     return 0;   }   