#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  char s[2000], t[2000];
  scanf("%d%d", &n, &m);
  scanf(" %s %s", s, t);
  int same[2000] = {0};
  for (int i = 0; i <= m - n; i++) {
    for (int j = i; j < i + n; j++) {
      if (s[j - i] == t[j]) same[i]++;
    }
  }
  int idx = 0;
  for (int i = 0; i <= m - n; i++)
    if (same[idx] < same[i]) idx = i;
  int cnt = 0;
  for (int i = idx; i < idx + n; i++) {
    if (t[i] != s[i - idx]) cnt++;
  }
  printf("%d\n", cnt);
  for (int i = idx; i < idx + n; i++) {
    if (t[i] != s[i - idx]) printf("%d ", i + 1 - idx);
  }
  printf("\n");
  return 0;
}
