#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
  int A, B;
  cin >> A >> B;
  string a, b;
  cin >> a >> b;
  int p = 0, m = a.size();
  for (int i = 0; i + a.size() <= b.size(); i++) {
    int k = 0;
    for (int j = 0; j < a.size(); j++) {
      if (a[j] != b[i + j]) k++;
    }
    if (k < m) {
      m = k;
      p = i;
    }
  }
  vector<int> v;
  for (int i = 0; i < a.size(); i++) {
    if (a[i] != b[i + p]) v.push_back(i);
  }
  cout << v.size() << endl;
  for (int i = 0; i < v.size(); i++) {
    cout << v[i] + 1 << " ";
  }
  return 0;
}
