Find the sum of all left leaves in a given binary tree. Example: 这道题让我们求一棵二叉树的所有左子叶的和,那么看到这道题我们知道这肯定是考二叉树的遍历问题,那么最简洁的写法肯定是用递归,由于我们只需要累加左子叶 ...
题目如下: Given a binary tree, return the sum of values of its deepest leaves. Example : Constraints: The number of nodes in the tree is between and . The value of nodes is between and . 解题思路:我的方法是做两次遍历,第 ...
2019-12-29 08:58 0 224 推荐指数:
Find the sum of all left leaves in a given binary tree. Example: 这道题让我们求一棵二叉树的所有左子叶的和,那么看到这道题我们知道这肯定是考二叉树的遍历问题,那么最简洁的写法肯定是用递归,由于我们只需要累加左子叶 ...
Given a rooted binary tree, return the lowest common ancestor of its deepest leaves. Recall that: The node of a binary tree is a leaf ...
原题地址:http://oj.leetcode.com/problems/two-sum/ 题意:找出数组numbers中的两个数,它们的和为给定的一个数target,并返回这两个数的索引,注意这里的索引不是数组下标,而是数组下标加1。比如numbers={2,7,11,17}; target ...
原题地址:http://oj.leetcode.com/problems/4sum/ 题意:从数组中找到4个数,使它们的和为target。要求去重,可能有多组解,需要都找出来。 解题思路:一开始想要像3Sum那样去解题,时间复杂度为O(N^3),可无论怎么写都是Time Limited ...
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 ...
Given an array of integers, find two numbers such that they add up to a specific target number. The ...
Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three ...
Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C wher ...