Another Circular Progress? Imagine having a checklist whereby you want to display to users how far they are into that or a list of steps whereby you want to show the progress visually. …

A valid number can be split up into these components (in order): A decimal number or an integer. (Optional) An 'e' or 'E', followed by an integer. A decimal number can be split up into these components (in order): (Optional) A sign character (either '+' or '-'). One of the…

Given the root of a binary tree, then value v and depth d, you need to add a row of nodes with value v at the given depth d. The root node is at depth 1. The adding rule is: given a positive integer depth d, for each NOT null…

We define a harmonious array as an array where the difference between its maximum value and its minimum value is exactly 1. Given an integer array nums, return the length of its longest harmonious subsequence among all its possible subsequences. A subsequence of array is a sequence that can be…

Given two strings A and B of lowercase letters, return true if you can swap two letters in A so the result is equal to B, otherwise, return false. Swapping letters is defined as taking two indices i and j (0-indexed) such that i != j and swapping the characters…

Given head, the head of a linked list, determine if the linked list has a cycle in it. There is a cycle in a linked list if there is some node in the list that can be reached again by continuously following the next pointer. Internally, pos is used to…

Given the root of a binary search tree and the lowest and highest boundaries as low and high, trim the tree so that all its elements lies in [low, high]. Trimming the tree should not change the relative structure of the elements that will remain in the tree (i.e., any…

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 integer type. In this case, the input will be given as a signed integer…

Today, we will be looking at the following problem listed as hard with an acceptance rate of 38.6% at the time of writing. The problem goes as follows: Given the root of a binary tree, calculate the vertical order traversal of the binary tree. For each node at position (row…