#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, ed[26][26] = {}, pos[26][26] = {};
  static char s[200100], t[200100];
  scanf("%d%s%s", &n, s, t);
  int ans = 0;
  for (int i = 0; i < (n); ++i) {
    ans += s[i] != t[i];
    ed[s[i] - 'a'][t[i] - 'a'] += 1;
    pos[s[i] - 'a'][t[i] - 'a'] = i + 1;
  }
  for (int i = 0; i < (26); ++i) {
    for (int j = 0; j < (i); ++j) {
      if (ed[j][i] && ed[i][j]) {
        printf("%d\n%d %d\n", ans - 2, pos[j][i], pos[i][j]);
        return 0;
      }
    }
  }
  for (int i = 0; i < (26); ++i) {
    for (int j = 0; j < (26); ++j) {
      if (j == i) continue;
      if (!ed[i][j]) continue;
      for (int k = 0; k < (26); ++k) {
        if (k != j && ed[j][k]) {
          printf("%d\n%d %d\n", ans - 1, pos[i][j], pos[j][k]);
          return 0;
        }
      }
    }
  }
  printf("%d\n%d %d\n", ans, -1, -1);
  return 0;
}
