func_code_string: #include <bits/stdc++.h>   using namespace std;   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     int64_t n, m;     cin >> n >> m;     pair<char, int64_t> a[n][m];     for (int64_t i = 0; i < n; ++i) {       for (int64_t j = 0; j < m; ++j) {         cin >> a[i][j].first;         a[i][j].second = 0;       }     }     for (int64_t i = 0; i < n; ++i) {       for (int64_t j = 0; j < m; ++j) {         int64_t c = 0;         for (int64_t k = 0; k < n; ++k) c += a[k][j].first == a[i][j].first;         if (c > 1) a[i][j].second = 1;         c = 0;         for (int64_t k = 0; k < m; ++k) c += a[i][j].first == a[i][k].first;         if (c > 1) a[i][j].second = 1;       }     }     for (int64_t i = 0; i < n; ++i) {       for (int64_t j = 0; j < m; ++j) {         if (a[i][j].second == 0) cout << a[i][j].first;       }     }   }   