Topcoder question 250 points (ANSWERS)

Problem Statement
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You are given a string input. you are to find the longest substring of input such that the reversal of the substring is also a substring of input. in case of a tie, return the string that occurs earliest in input.
Definition
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Class:
Reversesubstring
Method:
Findreversed
Parameters:
String
Returns:
String
Method signature:
String findreversed (string input)
(Be sure your method is public)
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Notes
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The substring and its reversal may overlap partially or completely.
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The entire original string is itself a valid substring (see example 4 ).
Constraints
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Input will contain between 1 and 50 characters, random Sive.
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Each character of input will be an uppercase letter ('A'-'Z ').
Examples
0)

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"Xbcdefywfedcbz"
Returns: "bcdef"
We see that the reverse of bcdef is fedcb, which appears later in the string.
1)

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"XYZ"
Returns: "X"
The best we can do is find a one character substring, So we implement the tie-breaker rule of taking the earliest one first.
2)

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"Abcaba"
Returns: "ABA"
The string ABA is a palindrome (it's its own reversal), so it meets the criteria.
3)

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"Fdasjkurekjfdfasireyufdhsajyirewq"
Returns: "FDF"

4)

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"Abcdcba"
Returns: "abcdcba"
Here, the entire string is its own reversal.
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