#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;   }   