Two Pointer on 111qqz's blog

leetcode 75. Sort Colors

Thu, 13 Apr 2017 12:02:02 +0000

Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue.

leetcode 11. Container With Most Water (two pointer)

Thu, 13 Apr 2017 10:13:01 +0000

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 water.

leetcode 16. 3Sum Closest (k-sum问题，two pointer)

Thu, 13 Apr 2017 09:45:45 +0000

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. You may assume that each input would have exactly one solution.

leetcode 18. 4Sum (k-sum问题，two pointer)

Thu, 13 Apr 2017 09:34:15 +0000

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.

leetcode 15. 3Sum (k-sum问题，two pointer)

Thu, 13 Apr 2017 08:21:52 +0000

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.