Unofficial C Solution to Problem 1.8 in Cracking the Coding Interview (5th Edition) | Code Says

Unofficial C Solution to Problem 1.8 in Cracking the Coding Interview (5th Edition) | Code Says

If string str1 is a rotation of string str2, it must holds two conditions:

1. The length of str1 equals to the length of str2;
2. There is at least a set of two string A and B, such that str1=AB and str2=BA. We double str1, and get a new string as ABAB. If str2 is a rotation of str1, str2 must be a substring of this new string.

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