func_code_string: #include <bits/stdc++.h>   using namespace std;   int N;   string s;   int pows[4] = {0, 0, 0, 0};   void Desc(int q) {     if (q <= 1) return;     switch (q) {       case 2:         pows[0]--;         break;       case 3:         pows[1]--;         break;       case 4:         pows[0] -= 2;         break;       case 5:         pows[2]--;         break;       case 6:         pows[0]--;         pows[1]--;         break;       case 7:         pows[3]--;         break;       case 8:         pows[0] -= 3;         break;       case 9:         pows[1] -= 2;         break;     }     Desc(q - 1);   }   void Proc(int q) {     if (q <= 1) return;     switch (q) {       case 2:         pows[0]++;         break;       case 3:         pows[1]++;         break;       case 4:         pows[0] += 2;         break;       case 5:         pows[2]++;         break;       case 6:         pows[0]++;         pows[1]++;         break;       case 7:         pows[3]++;         break;       case 8:         pows[0] += 3;         break;       case 9:         pows[1] += 2;         break;     }     Proc(q - 1);   }   int conv(int q) {     switch (q) {       case 0:         return 2;       case 1:         return 3;       case 2:         return 5;       case 3:         return 7;     }   }   int main() {     ios_base::sync_with_stdio(0);     cout.precision(20);     cin >> N;     cin >> s;     for (int i = 0; i < N; ++i) Proc(s[i] -  0 );     for (int i = 3; i >= 0; --i) {       while (pows[i] != 0) {         cout << conv(i);         Desc(conv(i));       }     }     return 0;   }   