func_code_string: #include <bits/stdc++.h>   using namespace std;   signed main(int argc, char const *argv[]) {     int t;     cin >> t;     while (t--) {       int n;       string s, k;       cin >> n;       cin >> s >> k;       int ans = 0;       string prev =  01 ;       for (int i = 0; i < n; i++) {         if ((s[i] ==  0  && k[i] ==  1 ) || (s[i] ==  1  && k[i] ==  0 )) {           prev =  01 ;           ans += 2;         } else if (s[i] ==  0  && k[i] ==  0 ) {           ans++;           if (prev ==  11 ) {             ans++;             prev =  01 ;           } else             prev =  00 ;         } else {           if (prev ==  00 ) {             ans++;             prev =  01 ;           } else             prev =  11 ;         }       }       cout << ans <<   n ;     }     return 0;   }   