#include <bits/stdc++.h>
using namespace std;
int N, M;
string s, t;
int main(int argc, const char* argv[]) {
  cin >> N >> M >> s >> t;
  int ind = 0;
  int min_syms = 1001;
  for (int i = 0; i <= M - N; i++) {
    int syms = 0;
    for (int j = 0; j < N; j++) {
      if (s[j] != t[i + j]) syms++;
    }
    if (syms < min_syms) {
      ind = i;
      min_syms = syms;
    }
  }
  cout << min_syms << endl;
  for (int i = 0; i < N; i++) {
    if (s[i] != t[ind + i]) cout << (i + 1) << " ";
  }
  cout << endl;
  return 0;
}
