#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using PII = pair<int, int>;
using PLL = pair<ll, ll>;
template <typename T1, typename T2>
ostream& operator<<(ostream& s, const pair<T1, T2>& p) {
  return s << "(" << p.first << ", " << p.second << ")";
}
template <typename T>
ostream& operator<<(ostream& s, const vector<T>& v) {
  s << "[";
  for (int i = 0; i < v.size(); i++) s << (i == 0 ? "" : ", ") << v[i];
  s << "]";
  return s;
}
int main() {
  int n, m;
  cin >> n >> m;
  string s, t;
  cin >> s >> t;
  int ans = (1 << 28);
  vector<int> ans_pos;
  for (int t_i = 0; t_i + s.size() <= t.size(); t_i++) {
    vector<int> pos;
    int cnt = 0;
    for (int i = 0; i < s.size(); i++) {
      if (s[i] != t[t_i + i]) {
        pos.push_back(i + 1);
        cnt++;
      }
    }
    if (ans > cnt) {
      ans = cnt;
      ans_pos = pos;
    }
  }
  cout << ans << endl;
  for (int i = 0; i < ans; i++) {
    cout << ans_pos[i] << " ";
  }
  cout << endl;
  return 0;
}
