摘要：
Given a linked list, remove the nth node from the end of list and return its head. 阅读全文
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Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target. 阅读全文
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Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. 阅读全文
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Write a function to find the longest common prefix string amongst an array of strings. 阅读全文
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Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. 阅读全文
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Given a roman numeral, convert it to an integer. 阅读全文
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Given an integer, convert it to a roman numeral. 阅读全文
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Implement regular expression matching with support for '.' and '*'. 阅读全文
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Given n non-negative integers a1, a2, ..., an, where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints of line i is at (i, ai) and (i, 0). Find two lines, which together with x-axis forms a container, such that the container contains the most wa... 阅读全文
摘要：
Determine whether an integer is a palindrome. Do this without extra space. 阅读全文