func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long int N = 1e5;   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     long long int tc = 1;     for (long long int T = 1; T <= tc; T++) {       long long int n;       cin >> n;       string s;       cin >> s;       long long int cnt = 0, flag = 0;       for (long long int i = 0; i < n - 1; i++) {         if (s[i] == s[i + 1] and s[i] !=  ? ) {           flag = 1;           break;         }       }       if (flag) {         cout <<  No n ;         return 0;       }       if (s[0] ==  ?  or s[n - 1] ==  ? ) {         cout <<  Yes n ;         return 0;       }       long long int tot = 0, ok = 0;       char start =  $ , end =  $ ;       for (long long int i = 0; i < n; i++) {         if (s[i] !=  ?  and flag == 0) {           start = s[i];         } else if (s[i] ==  ? ) {           cnt++;           flag = 1;         } else {           end = s[i];           if (cnt == 1) {             if (start == end) {               ok = 1;               break;             }           } else {             ok = 1;             break;           }           start = end;           cnt = 0;           flag = 0;         }       }       if (ok)         cout <<  Yes n ;       else         cout <<  No n ;     }     return 0;   }   