Problem:
Score : 400 points

Problem Statement

Given a string t, we will call it unbalanced if and only if the length of t is at least 2, and more than half of the letters in t are the same. For example, both voodoo and melee are unbalanced, while neither noon nor a is.

You are given a string s consisting of lowercase letters. Determine if there exists a (contiguous) substring of s that is unbalanced. If the answer is positive, show a position where such a substring occurs in s.

Constraints

2 ≦ |s| ≦ 10^5

s consists of lowercase letters.

Partial Score

200 points will be awarded for passing the test set satisfying 2 ≦ N ≦ 100.

Input

The input is given from Standard Input in the following format:

s

Output

If there exists no unbalanced substring of s, print -1 -1.

If there exists an unbalanced substring of s, let one such substring be s_a s_{a+1} ... s_{b} (1 ≦ a < b ≦ |s|), and print a b. If there exists more than one such substring, any of them will be accepted.

Sample Input 1

needed

Sample Output 1

2 5

The string s_2 s_3 s_4 s_5 = eede is unbalanced. There are also other unbalanced substrings. For example, the output 2 6 will also be accepted.

Sample Input 2

atcoder

Sample Output 2

-1 -1

The string atcoder contains no unbalanced substring.

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;
#define ll long long

bool check(char ch, string s) {
  for(int i=0; i<s.size(); i++) {
    if(s.at(i)==ch) {
      if(i+1<s.size()) {
	if(s.at(i+1)==ch) {
	  cout << i+1 << " " << i+2 << endl;
	  return true;
	}
      }
      if(i+2<s.size()) {
	int cnt = 0;
	if(s.at(i+1)==ch) cnt++;
	if(s.at(i+2)==ch) cnt++;
	if(cnt>1) {
	  cout << i+1 << " " << i+3 << endl;
	  return true;
	}
      }
    }
  }
  return false;
}

int main() {
  string s;
  cin >> s;
  set<char> charset;
  for(int i=0;i<s.size(); i++) {
    charset.insert(s.at(i));
  }
  for(char ch : charset) {
    if(check(ch, s)) {
      return 0;
    }
  }
  cout << "-1 -1" << endl;
  return 0;
}