JOIN

 Problem Statement

Problem Statement for BearPair

### Problem Statement

Bear Limak loves algorithms, especially the ones with words and strings.

Limak's friend recently entered a programming competition and wrote a program. The program contains a string constant s. Limak would now like to challenge the program by making it exceed the time limit. To do that, he must find two different characters in s that are as far apart as possible.

Formally, Limak must find two integers i and j with the following properties:

• Both i and j must be valid indices into s. That is, both numbers must be between 0 and n-1, inclusive, where n is the length of s.
• The characters s[i] and s[j] must be different.
• The difference between i and j must be as large as possible.

You are given the String s. If Limak cannot choose any integers with the required properties, return -1. Otherwise, return the largest possible difference between i and j.

### Definition

 Class: BearPair Method: bigDistance Parameters: String Returns: int Method signature: int bigDistance(String s) (be sure your method is public)

### Constraints

-s will have between 2 and 50 characters, inclusive.
-Each character in s will be a lowercase English letter ('a' - 'z').

### Examples

0)

 `"bear"`
`Returns: 3`
 Limak can choose the (0-based) indices 0 and 3. We have s[0]='b' and s[3]='r', which are indeed two different letters. The difference between the two indices is 3-0 = 3.
1)

 `"abcba"`
`Returns: 3`
 Here, one optimal solution is for Limak to choose the indices 1 and 4 (corresponding to 'b' and 'a', respectively). Another optimal solution is to choose indices 0 and 3 (letters 'a' and 'b'). In both cases the difference is 3.
2)

 `"oooohyeahpotato"`
`Returns: 13`
3)

 `"zzzzzzzzzzzzzzzzzzzzz"`
`Returns: -1`
 Here, Limak can't choose two indices with different letters.
4)

 `"qw"`
`Returns: 1`
5)

 `"xxyyxyxyyyyyyxxxyxyxxxyxyxyyyyyxxxxxxyyyyyyyyxxxxx"`
`Returns: 47`

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This problem was used for:
Single Round Match 680 Round 1 - Division II, Level One