#include <bits/stdc++.h>
using namespace std;
int idx[1010] = {0}, o[1010] = {0};
int main() {
  int n, m, i, j, c = 0, p, flag, min = 100000;
  cin >> n >> m;
  char s[1010], t[1010];
  cin >> s;
  cin >> t;
  p = 0;
  for (i = 0; i < m - n + 1; i++) {
    for (j = 0; j < n; j++) {
      if (s[j] != t[i + j]) {
        o[p]++;
      }
    }
    if (min > o[p]) {
      min = o[p];
      flag = i;
    }
    p++;
  }
  cout << min << endl;
  for (i = 0; i < n; i++) {
    if (s[i] != t[i + flag]) cout << i + 1 << " ";
  }
  return 0;
}
