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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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Given an integer, write a function to determine if it is a power of three. Follow up:Could you do it without using any loop / recursion? Credits:Speci 阅读全文
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Write a program to check whether a given number is an ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For exa 阅读全文
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Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. For example: Given num = 38, the process is like: 阅读全文
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Given an integer, write a function to determine if it is a power of two. Credits:Special thanks to @jianchao.li.fighter for adding this problem and cr 阅读全文
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Write an algorithm to determine if a number is "happy". A happy number is a number defined by the following process: Starting with any positive intege 阅读全文
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Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: 阅读全文
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Eclipse在保存代码时，总是自动换行。尤其是注释，换行后的注释读起来就很混乱。后来发现是在保存文件时设置了自动格式化代码的原因。 关闭自动格式代码设置： windows-->Preferences-->Java --> Editor-->Save Actions 去掉Format source 阅读全文
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Given a linked list, determine if it has a cycle in it. Follow up:Can you solve it without using extra space? 题意：给定一个链表，判断链表中是否存在环路。 注：不能使用额外的空间 思路：百度 阅读全文
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Given a sorted linked list, delete all duplicates such that each element appear only once. For example,Given 1->1->2, return 1->2.Given 1->1->2->3->3, 阅读全文