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Can minimum number of rotations required to get the same string be greater than len/2 and less than len ever?
By yesnomaybe, history, 4 years ago, In English

Given string S, and let K be the minimum number of rotations required to get the same string.

For Example: (1) For S = "aaaa", K = 1 (2) For S = "abcabc", K = 3 (3) For S = "abcdef", K = 6

Now my question is, can there be any string for which K > len(S)/2 and K < len(S) ? If not, can someone please help me prove it?

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4 years ago, # |
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In your example (3), K is greater than len(S) / 2.

You asked the wrong question?

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    4 years ago, # ^ |
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    Sorry I asked the wrong question. Have updated the question now. Can you please check? Can K > len(S)/2 && K < len(S)?

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4 years ago, # |
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Auto comment: topic has been updated by yesnomaybe (previous revision, new revision, compare).

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4 years ago, # |
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Auto comment: topic has been updated by yesnomaybe (previous revision, new revision, compare).

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4 years ago, # |
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Not possible, because K can only be divisor of N, and there is no such divisor greater than N/2 and less than N.

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    4 years ago, # ^ |
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    Can you please share the intuition behind why K needs to be divisor of N?

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      4 years ago, # ^ |
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      Sorry, can't share the intuition because I just realised that this question is being asked in google foobar challenge.(Almost same with different story)

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