#include <bits/stdc++.h>
int pd[1005][1005], k[100001];
using namespace std;
int main() {
  string a, b, ms, q;
  int m, n, t = 0, ans = 100000, z = 1;
  cin >> m >> n;
  cin >> a >> b;
  for (int i = 0; i <= n - m; i++) {
    string c = b.substr(i, m);
    for (int j = 0; j < m; j++) {
      if (c[j] != a[j]) {
        t++;
        k[z] = j + 1;
        z++;
      }
    }
    for (int h = 1; h <= z; h++) {
      pd[t][h] = k[h];
    }
    ans = min(t, ans);
    t = 0;
    z = 1;
  }
  if (ans == 100000) {
    cout << m << endl;
    for (int i = 1; i <= m; i++) cout << i << " ";
    return 0;
  }
  cout << ans << "\n";
  for (int i = 1; i <= ans; i++) {
    cout << pd[ans][i] << ' ';
  }
  cout << endl;
  return 0;
}
