#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(0);
  string s, t;
  int a, b;
  cin >> a >> b;
  cin >> s >> t;
  int ans = a + 100, st;
  for (int i = 0, __ = b; i < __; i++) {
    if (i + a - 1 >= b) break;
    int c = 0;
    for (int j = 0, __ = a; j < __; j++) {
      if (s[j] == t[i + j]) ++c;
    }
    if (a - c < ans) {
      st = i;
      ans = a - c;
    }
  }
  cout << ans << endl;
  for (int j = 0, __ = a; j < __; j++) {
    if (s[j] != t[st + j]) cout << j + 1 << ' ';
  }
  cout << endl;
  return 0;
}
