Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. …
Convert a Roman numeral value (ranged from 1 to 3999) to Arabic integer. Letter by Letter Conversion from Roman to Arabic The first few Roman numbers are: I, II, …
Write a function that takes an unsigned integer and returns the number of ’1′ bits it has (also known as the Hamming weight). For example, the 32-bit integer ’11′ …
Given a binary tree root, return whether it’s a binary search tree. A binary tree node is a binary search tree if : All nodes on its left subtree …
Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two …
Given two binary strings, return their sum (also a binary string). For example, a = “11” b = “1” Return “100”. It looks easy however may not seem so: …
