func_code_string: #include <bits/stdc++.h>   using namespace std;   template <class c>   struct rge {     c b, e;   };   template <class c>   rge<c> range(c i, c j) {     return rge<c>{i, j};   }   template <class c>   auto dud(c *x) -> decltype(cerr << *x, 0);   template <class c>   char dud(...);   struct debug {     template <class c>     debug &operator<<(const c &) {       return *this;     }   };   void solve() {     int n;     cin >> n;     string a, b;     cin >> a >> b;     vector<int> res;     for (int i = 0; i < a.length(); ++i) {       if (a[i] != b[i]) {         if (i > 0) res.push_back(i + 1);         res.push_back(1);         if (i > 0) res.push_back(i + 1);       }     }     cout << (int)res.size() <<    ;     for (long long i = 0; i < int((int)res.size()); i++) cout << res[i] <<    ;     cout <<   n ;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int t;     cin >> t;     while (t--) solve();   }   