func_code_string: #include <bits/stdc++.h>   using namespace std;   template <class c>   struct rge {     c b, e;   };   template <class c>   rge<c> range(c i, c j) {     return rge<c>{i, j};   }   template <class c>   auto dud(c* x) -> decltype(cerr << *x, 0);   template <class c>   char dud(...);   struct debug {     template <class c>     debug& operator<<(const c&) {       return *this;     }   };   const long long xx = 2e7;   const long long MOD = 1e9 + 7;   const long long inf = 1e18;   long long isprime(long long n) {     if (n == 2) return 1;     if (n % 2 == 0) return 0;     for (long long i = 3; i * i <= n; i += 2) {       if (n % i == 0) return 0;     }     return 1;   }   signed main() {     ios::sync_with_stdio(false);     cin.tie(0);     long long n;     cin >> n;     if (isprime(n)) {       cout << 1 <<   n ;     } else if (n % 2 == 0 || isprime(n - 2)) {       cout << 2 <<   n ;     } else       cout << 3 <<   n ;   }   