func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long int mod = 1e9 + 7;   long long x, k;   long long qow(long long a, long long b) {     long long ans = 1;     a = a % mod;     while (b) {       if (b % 2 == 1) {         ans = (ans * a) % mod;       }       a = (a * a) % mod;       b /= 2;     }     return ans;   }   int main() {     while (~scanf( %lld %lld , &x, &k)) {       if (x == 0) {         printf( 0 n );         continue;       }       x = x % mod;       cout << (((2 * x - 1) * qow(2, k) + mod) % mod + 1 + mod) % mod << endl;     }     return 0;   }   