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cyclic palindrome problem
By saket9450, history, 9 years ago, In English

hacker rank problem can any one please give me some hint to solve this problem

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9 years ago, # |
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If the input is small enough (constraints aren't specified), you can just append another copy of S to the back of it and check all substrings of length |S|. If you find a palindrome at position i (counting from 0), then the required number of shifts is min(|S| - i, i). Output the minimum among all of them.

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    9 years ago, # ^ |
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    Check every substring of length |S| .....by what ....using hash?

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      9 years ago, # ^ |
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      No, character by character with one pointer from each end. It'd be costly, that's why I said if constraints are small enough. I'd need to try to be sure, since they aren't specified in the problem statement.

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      9 years ago, # ^ |
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      hashes, Manacher's algorithm or palindromic tree

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    9 years ago, # ^ |
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    thanks for help tenshi_kanade i got it :D .

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