func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, m, k, c, ans = 0;     string s;     cin >> s;     bool sol = 1;     for (int i = 0; i < s.length(); i++) {       if (s[i] ==  1  && s[i + 1] ==  4  && s[i + 2] ==  4 ) {         i += 2;         continue;       }       if (s[i] ==  1  || (s[i] ==  4  && s[i - 1] ==  1 ))         continue;       else         sol = 0;     }     if (sol)       cout <<  YES ;     else       cout <<  NO ;     return 0;   }   