#include <bits/stdc++.h>
int main() {
  int n, m, result = 1010, startPos = 0;
  char s[1001], t[1001];
  scanf("%d %d", &n, &m);
  scanf("%s %s", s, t);
  for (int i = 0; i <= m - n; i++) {
    int count = 0;
    for (int j = 0; j < n; j++) {
      if (s[j] != t[i + j]) {
        count++;
      }
    }
    if (result > count) {
      result = count;
      startPos = i;
    }
  }
  printf("%d\n", result);
  for (int i = 0; i < n; i++) {
    if (s[i] != t[startPos + i]) {
      printf("%d ", i + 1);
    }
  }
  printf("\n");
}
