#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, m, ans = INT_MAX, pos;
  cin >> n >> m;
  string s, t;
  cin >> s >> t;
  for (long long int i = 0; i < m - n + 1; i++) {
    long long int c = 0;
    for (long long int j = 0; j < n; j++) {
      if (s[j] != t[i + j]) c++;
    }
    if (c < ans) {
      ans = c;
      pos = i;
    }
  }
  cout << ans << endl;
  for (long long int i = 0; i < n; i++) {
    if (s[i] != t[pos + i]) {
      cout << i + 1 << " ";
    }
  }
  return 0;
}
