#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  while (cin >> n >> m) {
    string s, t;
    cin >> s >> t;
    vector<int> res;
    bool f = true;
    for (int i = 0; i < m - n + 1; i++) {
      vector<int> tmp;
      for (int j = 0; j < n; j++) {
        if (s[j] != t[i + j]) tmp.push_back(j + 1);
      }
      if (f)
        f = false, res = tmp;
      else if (tmp.size() < res.size())
        res = tmp;
    }
    cout << res.size() << endl;
    for (int i = 0; i < res.size(); i++) cout << res[i] << " ";
    cout << endl;
  }
  return 0;
}
