func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n;     scanf( %d , &n);     bool F = 1;     for (int i = 2; (long long)i * i <= n; i++) {       if (n % i == 0) {         F = 0;         break;       }     }     bool F2 = 1;     for (int i = 2; (long long)i * i <= n - 2; i++) {       if ((n - 2) % i == 0) {         F2 = 0;         break;       }     }     printf( %d n , F ? 1 : n % 2 == 0 || F2 ? 2 : 3);     return 0;   }   