#include <bits/stdc++.h>
int l, cnt, ht[2000], x1, x2, id, con = -1, id2 = -1, ss[26], tt[26];
char s[200005], t[200005];
bool ch;
int hsh(int m, char x, char y) {
  return m * 676 + ((int)x - (int)'a') * 26 + ((int)y - (int)'a');
}
int main() {
  memset(ss, -1, sizeof(ss));
  memset(tt, -1, sizeof(tt));
  memset(ht, -1, sizeof(ht));
  scanf("%d", &l);
  scanf("%s%s", s, t);
  for (int i = 0; i < l; i++) {
    if (s[i] != t[i]) {
      cnt++;
      con = id2;
      id2 = i;
      ss[s[i] - 'a'] = i;
      tt[t[i] - 'a'] = i;
      if (!ch) {
        ht[hsh(0, s[i], t[i])] = i;
        if (ht[hsh(1, s[i], t[i])] != -1 && ht[hsh(1, s[i], t[i])] != i) {
          id = i;
          ch = true;
        }
        if (ch) continue;
        ht[hsh(1, t[i], s[i])] = i;
        if (ht[hsh(0, t[i], s[i])] != -1 && ht[hsh(0, t[i], s[i])] != i) {
          id = i;
          ch = true;
        }
      }
    }
  }
  if (ht[hsh(0, s[id], t[id])] != -1 && ht[hsh(1, s[id], t[id])] != -1 &&
      ht[hsh(1, s[id], t[id])] != ht[hsh(0, s[id], t[id])])
    printf("%d\n%d %d", cnt - 2, ht[hsh(0, s[id], t[id])] + 1,
           ht[hsh(1, s[id], t[id])] + 1);
  else if (id2 == -1 || con == -1)
    printf("%d\n-1 -1", cnt);
  else {
    id2 = -1;
    con = -1;
    for (int i = 0; i < 26; i++) {
      if (ss[i] != -1 && tt[i] != -1) {
        id2 = ss[i];
        con = tt[i];
        break;
      }
    }
    if (id2 == -1)
      printf("%d\n-1 -1", cnt);
    else
      printf("%d\n%d %d", cnt - 1, id2 + 1, con + 1);
  }
  return 0;
}
