#include <bits/stdc++.h>
using namespace std;
char s1[1005], s2[1005];
int l1, l2, ans, pos, ma;
int main() {
  scanf("%d%d", &l1, &l2);
  scanf("%s%s", s1, s2);
  ma = 0;
  for (int i = 0; i < l2 - l1 + 1; i++) {
    ans = 0;
    for (int j = 0; j < l1; j++)
      if (s2[i + j] == s1[j]) ans++;
    if (ma < ans) ma = ans, pos = i;
  }
  printf("%d\n", l1 - ma);
  for (int i = 0; i < l1; i++)
    if (s1[i] != s2[pos + i]) printf("%d ", i + 1);
  printf("\n");
  return 0;
}
