func_code_string: #include <bits/stdc++.h>   using namespace std;   long long fib[50010];   int main() {     long long n;     cin >> n;     fib[0] = 1;     fib[1] = 2;     if (n == 1) {       cout << 0;       return 0;     } else if (n == 2) {       cout << 1;       return 0;     }     int i = 1;     while (fib[i] <= n) {       ++i;       fib[i] = fib[i - 2] + fib[i - 1];     }     --i;     cout << i;   }   