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 REP(i,s,n) for(int i=s;i<n;++i)
#define rep(i,n) REP(i,0,n)
#define SORT(c) sort((c).begin(),(c).end())
#define IINF INT_MAX
#define LLINF LLONG_MAX
#define DEBUG false

typedef long long ll;
typedef pair<int, int> ii;

int main() {

	string s;
	cin >> s;

	vector<vector<int>> pos(26);
	rep(i, s.size()){
		pos[s[i] - 'a'].push_back(i+1);
	}

	int ansr = -1, ansl = -1;
	rep(i, 26){
		int r = 0;
		REP(l, 1, pos[i].size()){
			while((r + 1 < l) && (pos[i][l] - pos[i][r] + 1)*(l - r) >= (pos[i][l] - pos[i][r+1] + 1) * (l - r + 1)) r++;
			//cout << r << " " << l << endl;
			if((l != r) && (l - r + 1) * 2 >= (pos[i][l] - pos[i][r] + 1)) {
				ansl = pos[i][l];
				ansr = pos[i][r];
			}
		}
	}

	cout << ansr << " " << ansl << endl;

	return 0;
}