#include <bits/stdc++.h>
using namespace std;
int n, m;
string s, t;
int ans = 10000, p[1010], q[1010];
void work(int k) {
  int tot = 0;
  for (int i = 0; i < s.length(); i++, k++)
    if (s[i] != t[k]) q[++tot] = i + 1;
  if (tot < ans) {
    ans = tot;
    for (int i = 1; i <= tot; i++) p[i] = q[i];
  }
}
int main() {
  scanf("%d%d", &n, &m);
  cin >> s >> t;
  for (int i = 0; i <= t.length() - s.length(); i++) work(i);
  cout << ans << endl;
  for (int i = 1; i <= ans; i++) printf("%d ", p[i]);
  return 0;
}
