Given an array of meeting time intervals where intervals[i] = [start, end], determine if a person could attend all meetings. Example 1:Input: intervals = [[0,30],[5,10],[15,20]]Output: false

Given a sorted array of distinct integers and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order. You must write an algori

Given an array of citations (each citation is a non-negative integer) of a researcher, write a function to compute the researcher’s h-index. According to the definition of h-index on Wikipedia: “A sci

Given an integer array nums, move all 0’s to the end of it while maintaining the relative order of the non-zero elements. Note that you must do this in-place without making a copy of the array. Exampl

The DNA sequence is composed of a series of nucleotides abbreviated as ‘A’, ‘C’, ‘G’, and ‘T’. For example, “ACGAATTCCG” is a DNA sequence. When studying DNA, it is useful to identify repeated sequenc

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

Write a function that takes an unsigned integer and returns the number of ‘1’ bits it has (also known as the Hamming weight). Note:Note that in some languages, such as Java, there is no unsigned integ

Given the head of a singly linked list, reverse the list, and return the reversed list. Example 1:Input: head = [1,2,3,4,5]Output: [5,4,3,2,1] Example 2:Input: head = [1,2]Output: [2,1] Exam

Write an algorithm to determine if a number n is happy. A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes contains a single digit. Add the two numbers and return