#include <bits/stdc++.h>
using namespace std;
const int Max1 = 1e5 + 4;
const int Max2 = 2e5 + 4;
const int Mod = 1e9 + 7;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int sl, tl;
  cin >> sl >> tl;
  string s, t;
  cin >> s >> t;
  vector<string> v;
  vector<vector<int> > freq(1004);
  for (int i = 0; i < tl - sl + 1; i++) {
    string m = "";
    for (int j = 0; j < sl; j++) {
      m += t[i + j];
    }
    v.push_back(m);
  }
  for (int i = 0; i < v.size(); i++) {
    for (int j = 0; j < sl; j++) {
      if (s[j] != v[i][j]) {
        freq[i].push_back(j + 1);
      }
    }
  }
  int min_sz = INT_MAX;
  int idx;
  for (int i = 0; i < v.size(); i++) {
    if (freq[i].size() < min_sz) {
      min_sz = freq[i].size();
      idx = i;
    }
  }
  vector<int> ans = freq[idx];
  cout << ans.size() << "\n";
  for (int i : ans) cout << i << " ";
  cout << "\n";
}
