Two Pointers

[Leetcode] Trapping Rain Water

While the concept is two pointers converging from opposite sides, the implementation is more in a dp form.

Description

Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how…

[Leetcode] Find K Closest Elements

A rarely seen pattern of two pointers.

Description

Given a sorted integer array arr, two integers k and x, return the k closest integers to x in the array. The result should also be sorted in ascending order.

[Leetcode] Backspace String Compare

An intuitively challenging paractice for two pointers.

Description

Given two strings s and t, return true if they are equal when both are typed into empty text editors. '#' means a backspace character.

[Leetcode] 3Sum

It’s all about two pointers.

Description

Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nums[j] + nums[k] == 0.

[Leetcode] Longest Repeating Character Replacement

[Leetcode] Find Minimum in Rotated Sorted Array

Use binary search to locate pivot of rotation.

Description

Suppose an array of length n sorted in ascending order is rotated between 1 and n times. For example, the array nums = [0,1,2,4,5,6,7]…

[Leetcode] Container With Most Water

A classic practice for two pointers.

Description

[Leetcode] Merge Intervals

Not conspicuous at first but two pointer could be helpful.

Description