摘要:
Given a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtree of a node contains only n... 阅读全文
摘要:
Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum.For example:Given the below binary tree andsum =... 阅读全文
摘要:
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.Fo... 阅读全文
摘要:
Given an array of integers, find two numbers such that they add up to a specific target number.The function twoSum should return indices of the two nu... 阅读全文
摘要:
Given an array of non-negative integers, you are initially positioned at the first index of the array.Each element in the array represents your maximu... 阅读全文
摘要:
Spiral Matrix IIGiven an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. For example,Given n = 3,You should ret... 阅读全文