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 Rust (1.15.1) (judge verdict: Accepted)

fn main() {
    let s: String = {
        let mut buffer = String::new();
        std::io::stdin().read_line(&mut buffer).unwrap();

        buffer.trim().to_string()
    };

    let mut unbalanced = None;
    let mut mae = (None, None);

    for (i, c) in s.chars().enumerate() {
        if let Some(mc) = mae.0 {
            if mc == c {
                unbalanced = Some((i - 1, i));
                break;
            }
        }

        if let Some(mc) = mae.1 {
            if mc == c {
                unbalanced = Some((i - 2, i));
                break;
            }
        }

        mae.1 = mae.0;
        mae.0 = Some(c);
    }

    if let Some((i, j)) = unbalanced {
        println!("{} {}", i + 1, j + 1);
    } else {
        println!("-1 -1");
    }
}