func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n, k;     cin >> n >> k;     string s[n];     set<string> store;     for (int i = 0; i < n; i++) {       cin >> s[i];       store.insert(s[i]);     }     int cnt = 0;     for (int i = 0; i < n; i++) {       set<string> v;       store.erase(s[i]);       for (int j = i + 1; j < n; j++) {         v.insert(s[j]);         store.erase(s[j]);         string temp;         for (int l = 0; l < k; l++) {           if (s[i][l] == s[j][l]) {             temp += s[i][l];           } else {             temp += ( S  +  E  +  T  - s[i][l] - s[j][l]);           }         }         if (store.find(temp) != store.end()) {           cnt++;           v.insert(temp);           store.erase(temp);         }       }       for (auto it : v) {         store.insert(it);       }     }     cout << cnt <<   n ;   }   