func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     char str[8][10];     int n, k, i, j, l, mx, mn, mind;     int p[] = {1, 2, 3, 4, 5, 6, 7, 8};     cin >> n >> k;     for (i = 0; i < n; i++) cin >> str[i];     mx = 0;     mn = 1000000000;     mind = mn - mx;     do {       int arr[8] = {0};       mx = 0;       mn = 1000000000;       for (i = 0; i < n; i++) {         for (j = 0; j < k; j++) {           arr[i] *= 10;           arr[i] += (int)(str[i][p[j] - 1] -  0 );         }         if (arr[i] > mx) mx = arr[i];         if (arr[i] < mn) mn = arr[i];       }       mind = min(mind, (mx - mn));     } while (std::next_permutation(p, p + k));     cout << mind << endl;     return 0;   }   