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问题描述 Suppose we abstract our file system by a string in the following manner: The string "dir\n\tsubdir1\n\tsubdir2\n\t\tfile.ext" represents: dir sub 阅读全文
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问题描述 Given a string, find the first non repeating character in it and return it's index. If it doesn't exist, return 1. Examples: s = "leetcode" retur 阅读全文
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问题描述 Given an integer n, return 1 n in lexicographical order. For example, given 13, return: [1,10,11,12,13,2,3,4,5,6,7,8,9]. Please optimize your alg 阅读全文