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Formation is very important when taking a group photo. Given the rules of forming K rows with N people as the following: The number of people in each 阅读全文
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The basic task is simple: given N real numbers, you are supposed to calculate their average. But what makes it complicated is that some of the input n 阅读全文
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When register on a social network, you are always asked to specify your hobbies in order to find some potential friends with the same hobbies. A socia 阅读全文
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A supply chain is a network of retailers（零售商）, distributors（经销商）, and suppliers（供应商） everyone involved in moving a product from supplier to customer. 阅读全文
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This time your job is to fill a sequence of N positive integers into a spiral matrix in non increasing order. A spiral matrix is filled in from the fi 阅读全文
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Given a sequence of positive numbers, a segment is defined to be a consecutive subsequence. For example, given the sequence {0.1, 0.2, 0.3, 0.4}, we h 阅读全文
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The K P factorization of a positive integer N is to write N as the sum of the P th power of K positive integers. You are supposed to write a program t 阅读全文
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The following is from Max Howell @twitter: Google: 90% of our engineers use the software you wrote (Homebrew), but you can't invert a binary tree on a 阅读全文
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There is a classical process named partition in the famous quick sort algorithm. In this process we typically choose one element as the pivot. Then th 阅读全文