func_code_string: #include <bits/stdc++.h>   using namespace std;   bool compare(const pair<int, int>& i, const pair<int, int>& j) {     return i.first < j.first;   }   int main() {     string r, s;     cin >> r >> s;     vector<int> v;     if (r.length() != s.length()) {       cout <<  NO             <<   n ;       return 0;     }     for (int i = 0; i < s.length(); i++) {       if (s[i] != r[i]) {         v.push_back(i);       }     }     if (v.size() != 2)       cout <<  NO             <<   n ;     else {       if (s[v[0]] == r[v[1]] && s[v[1]] == r[v[0]])         cout <<  YES ;       else         cout <<  NO ;     }     return 0;   }   