摘要：
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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Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at 阅读全文
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Given a string, find the first non-repeating character in it and return it's index. If it doesn't exist, return -1. Examples: Note: You may assume the 阅读全文
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Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function that will return true if the rans 阅读全文
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Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library functio 阅读全文
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Given two arrays, write a function to compute their intersection. Example 1: Example 2: Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4] Output: [9,4] Exam 阅读全文