func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 100000 + 10;   const int M = 1000000007;   const double PI = atan(1) * 4;   const int oo = 1000000000;   long long A, B, n, x;   long long pw(long long x, long long p) {     if (!p) return 1;     long long d = pw(x, p / 2);     d = (d * d) % M;     if (p % 2) d = (d * x) % M;     assert(x <= M);     assert(d <= M);     return d;   }   int main() {     cin >> A >> B >> n >> x;     if (A == 1) return cout << (n % M * B % M + x) % M, 0;     long long one = x * pw(A, n) % M;     long long dom = pw(A, n) - 1;     long long den = pw(A - 1, M - 2);     cout << (one + B * ((dom * den) % M) % M) % M << endl;   }   