func_code_string: #include <bits/stdc++.h>   using namespace std;   long long powmod(long long a, long long b) {     if (b == 0) return 1;     long long x = powmod(a, b / 2);     long long y = (x * x) % 1000000007;     if (b % 2) return (a * y) % 1000000007;     return y % 1000000007;   }   long long mulmod(long long a, long long b, long long c) {     long long x = 0, y = a % c;     while (b > 0) {       if (b % 2 == 1) {         x = (x + y) % c;       }       y = (y * 2) % c;       b /= 2;     }     return x % c;   }   int main() {     long long a, b, x, n;     cin >> a >> b >> n >> x;     long long nm1, nm2, nm3, nm4, nm5;     if (a > 1) {       nm1 = powmod(a, n);       nm2 = (nm1 - 1 + 1000000007) % 1000000007;       nm3 = (x * nm1) % 1000000007;       nm4 = (a - 1 + 1000000007) % 1000000007;       nm5 = (nm2 * powmod(nm4, 1000000007 - 2)) % 1000000007;       long long nm6 = (nm3 + (nm5 * b) % 1000000007) % 1000000007;       cout << nm6 << endl;     } else       cout << (x + mulmod(b, n, 1000000007)) % 1000000007 << endl;     return 0;   }   