#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e3 + 10;
int n, m;
char s[MAXN], t[MAXN];
int main(int argc, const char* argv[]) {
  cin >> n >> m;
  cin >> (s + 1);
  cin >> (t + 1);
  int co = 0x7fffffff;
  int ans = 0;
  for (int i = 0; i <= m - n; i++) {
    int temp = 0;
    for (int j = 1; j <= n; j++) {
      if (s[j] != t[j + i]) {
        temp++;
      }
    }
    if (temp < co) {
      co = temp;
      ans = i;
    }
  }
  cout << co << endl;
  for (int j = 1; j <= n; j++) {
    if (s[j] != t[j + ans]) {
      cout << j << " ";
    }
  }
  cout << endl;
  return 0;
}
