#include <bits/stdc++.h>
using namespace std;
void solve() {
  int n;
  scanf("%d\n", &n);
  string a, b;
  getline(cin, a);
  getline(cin, b);
  int q(0);
  map<pair<char, char>, int> SET;
  map<char, int> have;
  for (int i(0), _l((int)(n)-1); i <= _l; ++i) {
    if (a[i] != b[i]) {
      ++q;
      SET[make_pair(a[i], b[i])] = i;
      have[a[i]] = i;
    }
  }
  int delta(0);
  pair<int, int> ans(-2, -2);
  for (int i(0), _l((int)(n)-1); i <= _l; ++i) {
    if (a[i] != b[i]) {
      if (have.count(b[i]) && delta == 0)
        delta = 1, ans = make_pair(i, have[b[i]]);
      if (SET.count(make_pair(b[i], a[i])))
        delta = 2, ans = make_pair(i, SET[make_pair(b[i], a[i])]);
    }
  }
  cout << q - delta << endl;
  cout << ans.first + 1 << " " << ans.second + 1 << endl;
}
int main() {
  solve();
  return 0;
}
