func_code_string: #include <bits/stdc++.h>   using namespace std;   long long int power(long long int base, long long int exp) {     long long int res = 1;     base = base % 1000000007;     while (exp) {       if (exp & 1) res = (res * base) % 1000000007;       base = (base * base) % 1000000007;       exp >>= 1;     }     return res;   }   int main() {     long long int n;     scanf( %lld , &n);     if (n == 0)       printf( 1 n );     else       printf( %lld n , power(2, n - 1) * (power(2, n) + 1) % 1000000007);     return 0;   }   