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Given a non-empty array of integers, return the third maximum number in this array. If it does not exist, return the maximum number. The time complexi 阅读全文
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Given a string representing an expression of fraction addition and subtraction, you need to return the calculation result in string format. The final 阅读全文
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Given the coordinates of four points in 2D space, return whether the four points could construct a square.The coordinate (x,y) of a point is represent 阅读全文
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We define a harmonious array is an array where the difference between its maximum value and its minimum value is exactly 1.Now, given an integer array 阅读全文
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Description:Count the number of prime numbers less than a non-negative number, n. 思路： 参考http://www.cnblogs.com/TonyYPZhang/p/5138018.html给出的方案以及wiki的方 阅读全文