问题叙述性说明: 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 integers. You may assume that each input would have exactly one solution. For example, given array S…

LeetCode:Path Sum 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. For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \…

Given an integer array, find a subarray with sum closest to zero. Return the indexes of the first number and last number. Have you met this question in a real interview? Yes Example Given [-3, 1, 1, -3, 5], return [0, 2], [1, 3], [1, 1], [2, 2] or [0…

问题:K Sum问题是一个问题系列,在一个数组中找K个数的和能够满足题目中要求.从2 Sum 到 3 Sum , 3 Sum Clozet , 4 Sum..解法虽一开始不容易想到,但get到解题技能后,该系列的题目其实解法较为单一. 一.核心解题思路.Two Sum. 题目:一个数组a中,找寻两个数,使其和等于target.返回两个数的下标. 思路:最白目的思路是O(n2)解法,无需多言.精彩的解法能够O(n)完成算法. 将该数组进行排序.设置两个指针start,end指向数组的头尾.如果a[…

Question Given an integer array, find a subarray with sum closest to zero. Return the indexes of the first number and last number. Given [-3, 1, 1, -3, 5], return [0, 2], [1, 3],[1, 1], [2, 2] or [0, 4]. Answer 这道题延续Subarray Sum的思路,即将[0, i]的sum存起来.这里…

LeetCode 16. 3Sum Closest(最接近的三数之和)…

剑指offer 65. 不用加减乘除做加法(Leetcode 371. Sum of Two Integers) https://leetcode.com/problems/sum-of-two-integers/ 题目: 写一个函数,求两个整数之和,要求在函数体内不得使用加减乘除这四个符号. 分析: 对于不能使用正常的四则运算符,一般就是使用位运算了.而本题要想实现加法,只能使用异或了. 需要注意的是,加法的时候涉及进位,而进位的实现利用与运算. 此外,进位之后还有可能产生进位,所以要在循环里…

Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution. Example: Given nums = [2, 7, 11, 15], target = 9, Because nums[0] + nums[1] = 2…

https://leetcode.com/problems/3sum-closest/ [描述] 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 integers. You may assume that each input would have exactly…

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 integers. You may assume that each input would have exactly one solution. For example, given array S = {-1 2…