func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     string s;     cin >> s;     int len = s.length();     for (int i = 0; i < len;) {       if (s[i] !=  1 ) {         cout <<  NO  << endl;         return 0;       }       if (i + 3 <= len) {         if (s[i + 1] ==  4  and s[i + 2] ==  4 ) {           i += 3;         } else if (s[i + 1] ==  4 ) {           i += 2;         } else           ++i;       } else if (i + 2 <= len) {         if (s[i + 1] ==  4 ) {           i += 2;         } else           ++i;       } else         ++i;     }     cout <<  YES  << endl;     return 0;   }   