func_code_string: #include <bits/stdc++.h>   using namespace std;   int power(int a, int n, int m) {     if (n <= 0) return 1;     if (n % 2 == 1) {       return ((int)(((long long)power(a, n - 1, m) * a) % m));     } else {       int k = power(a, n / 2, m);       return ((int)(((long long)k * k) % m));     }   }   int main() {     long long n, m;     cin >> n >> m;     long long ans = (power(3, n, m) - 1) % m;     if (ans < 0) ans += m;     cout << ans;     return 0;   }   