#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, mn = INT_MAX, curr;
  cin >> n >> m;
  string s, t;
  cin >> s >> t;
  vector<vector<int> > vec(1000);
  for (int i = 0; i < m; i++) {
    int cnt = 0, f = 0;
    for (int j = 0, c = i; j < n; j++, c++) {
      if (c == m) {
        vec[i].clear();
        f = 1;
        break;
      }
      if (s[j] != t[c]) {
        vec[i].push_back(j + 1);
        cnt++;
      }
    }
    if (mn > cnt && !f) {
      mn = cnt;
      curr = i;
    }
  }
  int k = vec[curr].size();
  cout << k << endl;
  for (int i = 0; i < k; i++) cout << vec[curr][i] << " ";
  return 0;
}
