#include <bits/stdc++.h>
using namespace std;
char s[1001];
char t[1001];
int main() {
  int lenS, lenT;
  scanf("%d %d", &lenS, &lenT);
  scanf(" %s %s", s, t);
  int minV = 1001;
  int minIdx = 0;
  for (int i = 0; i < lenT - lenS + 1; i++) {
    int diff = 0;
    for (int j = 0; j < lenS; j++) {
      if (s[j] != t[i + j]) diff++;
    }
    if (diff < minV) {
      minV = diff;
      minIdx = i;
    }
  }
  printf("%d\n", minV);
  for (int i = 0; i < lenS; i++) {
    if (s[i] != t[i + minIdx]) printf("%d ", i + 1);
  }
  return 0;
}
