#include <bits/stdc++.h>
using namespace std;
int a, b;
string s1, s2;
int main() {
  ios_base::sync_with_stdio(false);
  cin >> a >> b;
  cin >> s1 >> s2;
  int _min = a, _inx = 0;
  for (int i = 0; i < b - a + 1; ++i) {
    int _cur = 0;
    for (int i2 = i; i2 < i + a; ++i2) {
      if (s1[i2 - i] != s2[i2]) _cur++;
    }
    if (_cur < _min) {
      _min = _cur;
      _inx = i;
    }
  }
  cout << _min << endl;
  for (int i = 0; i < a; ++i) {
    if (s1[i] != s2[_inx + i]) cout << i + 1 << " ";
  }
  cout << endl;
  return 0;
}
