摘要：
Design a simplified version of Twitter where users can post tweets, follow/unfollow another user and is able to see the 10 most recent tweets in the u 阅读全文
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Find the nth digit of the infinite integer sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ... Note:n is positive and will fit within the range of a 32-bi 阅读全文
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Design a data structure that supports the following two operations: search(word) can search a literal word or a regular expression string containing o 阅读全文
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Implement a trie with insert, search, and startsWith methods. Note:You may assume that all inputs are consist of lowercase letters a-z. Show Company T 阅读全文
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Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and r 阅读全文
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Given an array of words and a length L, format the text such that each line has exactly L characters and is fully (left and right) justified. You shou 阅读全文