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Design and implement a TwoSum class. It should support the following operations: add and find. add - Add the number to an internal data structure.find 阅读全文
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这道题就是根据条件老老实实的做 阅读全文
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Given two strings s and t, determine if they are isomorphic. Two strings are isomorphic if the characters in s can be replaced to get t. All occurrenc 阅读全文
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Better idea is to maintain a hashset that contains at most k numbers 阅读全文
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Write a program to find the n-th ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 1, 2, 3, 4, 5, 阅读全文
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This is a follow up of Shortest Word Distance. The only difference is now word1 could be the same as word2. Given a list of words and two words word1 阅读全文
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This is a follow up of Shortest Word Distance. The only difference is now you are given the list of words and your method will be called repeatedly ma 阅读全文
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Given a list of words and two words word1 and word2, return the shortest distance between these two words in the list. For example,Assume that words = 阅读全文