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# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;

class Program
{
    static void Main(string[] args)
    {
        string s = Console.ReadLine();
        int check_wordcnt = 2;
        if (s.Length > 3)  check_wordcnt = 3;
        bool unbalance = false;

        while (check_wordcnt <= s.Length && unbalance == false)
        {
            int majority = check_wordcnt / 2 + 1;
            //Console.WriteLine(majority);
            for (int i = 0; i < s.Length - check_wordcnt+1; i++)
            {
                string checkword = s.Substring(i, check_wordcnt);
                //Console.WriteLine(checkword);
                unbalance = check(checkword,majority);
                if(unbalance == true)
                {
                    Console.WriteLine("{0} {1}", i + 1, check_wordcnt);
                    break;
                }
            }
            if (s.Length > check_wordcnt + 2) check_wordcnt++;
            check_wordcnt++;            
        }
        if (unbalance == false) Console.WriteLine("-1 -1");
    }

    static bool check(string checkword,int majority)
    {
        for (int i = 0; i < checkword.Length - 1;)
        {
            int samecnt = 1;
            for (int j = i + 1; j < checkword.Length; j++)
            {
                if (checkword[i] == checkword[j])
                {
                    samecnt++;
                    checkword = checkword.Remove(j, 1);
                }

            }
            checkword = checkword.Remove(0, 1);
            if (samecnt >= majority)
            {
                return true;
            }
        }
        return false;
    }

}