整体上3个题都是求subarray,都是同一个思想,通过累加,然后判断和目标k值之间的关系,然后查看之前子数组的累加和. map的存储:560题是存储的当前的累加和与个数 561题是存储的当前累加和的余数与第一次出现这个余数的位置 325题存储的是当前累加和与第一次出现这个和的位置 其实561与325都是求的最长长度,那就一定要存储的是第一次出现满足要求的位置,中间可能还出现这种满足要求的情况,但都不能进行存储 560. Subarray Sum Equals K 求和为k的连续子数组的个数 h…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址:https://leetcode.com/problems/subarray-sum-equals-k/description/ 题目描述 Given an array of integers and an integer k, you need to find the total number of continuous subar…

［抄题］: Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 [暴力解法]: 时间分析: 空间分析: [优化后]: 时间分析: 空间分析: ［奇葩输出条件］: ［奇葩corner case］: ［思维…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

题目如下:解题思路:本题的关键在于题目限定了是连续的数组,我们用一个dp数组保存第i位到数组末位的和.例如nums = [1,1,1],那么dp = [3,2,1], dp[i]表示nums[i]+nums[i+1] +...+nums[len(nums)-1],有了这一个dp数组后,我们很容易就可以得到递推表达式 sum(i,j) = dp[i] - dp[j+1].最后,顺序遍历dp数组,对于任意的dp[i],只要找到对应的dp[k-i]就可以了. 代码如下: class Solution(…

Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Example 1: Given nums = [1, -1, 5, -2, 3], k = 3,return 4. (because the subarray [1, -1, 5, -2] sums to 3 and is the…

Subarray Sum Given an integer array, find a subarray where the sum of numbers is zero. Your code should return the index of the first number and the index of the last number. Notice There is at least one subarray that it's sum equals to zero. Example…

Subarray Sum Given an integer array, find a subarray where the sum of numbers is zero. Your code should return the index of the first number and the index of the last number. Notice There is at least one subarray that it's sum equals to zero. Example…

原题链接在这里:https://leetcode.com/problems/continuous-subarray-sum/description/ 题目: Given a list of non-negative numbers and a target integer k, write a function to check if the array has a continuous subarray of size at least 2 that sums up to the multip…

题目描述 给定一个整数数组和一个整数 k,你需要找到该数组中和为 k 的连续的子数组的个数. 示例 1 : 输入:nums = [1,1,1], k = 2 输出: 2 , [1,1] 与 [1,1] 为两种不同的情况. 说明 : 数组的长度为 [1, 20,000]. 数组中元素的范围是 [-1000, 1000] ,且整数 k 的范围是 [-1e7, 1e7]. 解题思路 维护一个map,在遍历数组时,更新包含当前数字之前所有数的和出现的次数,这样每遍历到一个位置,将当前和减去k,若map中…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Example 1: Given nums = [1, -1, 5, -2, 3], k = 3, return 4. (because the subarray [1, -1, 5, -2] sums to 3 and is th…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Example 1: Given nums = [1, -1, 5, -2, 3], k = 3,return 4. (because the subarray [1, -1, 5, -2] sums to 3 and is the…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2  Note: The length of the array is in range [1, 20,000]. The range of number…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Note:The sum of the entire nums array is guaranteed to fit within the 32-bit signed integer range. Example 1: Given…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

Description Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The rang…

Level:   Medium 题目描述: Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]…

Given a list of non-negative numbers and a target integer k, write a function to check if the array has a continuous subarray of size at least 2 that sums up to the multiple of k, that is, sums up to n*k where n is also an integer. Example 1: Input:…

非负数组中找到和为K的倍数的连续子数组 详见:https://leetcode.com/problems/continuous-subarray-sum/description/ Java实现: 方法一: class Solution { public boolean checkSubarraySum(int[] nums, int k) { for(int i=0;i<nums.length;++i){ int sum=nums[i]; for(int j=i+1;j<nums.length…

Dynamic Programming There is a nice introduction to the DP algorithm in this Wikipedia article. The idea is to maintain a running maximum smax and a current summation sum. When we visit each num in nums, addnum to sum, then update smax if necessary o…

题目 原题链接 给定一个正整数数组 A,如果 A 的某个子数组中不同整数的个数恰好为 K,则称 A 的这个连续.不一定独立的子数组为好子数组. (例如,[1,2,3,1,2] 中有 3 个不同的整数:1,2,以及 3.) 返回 A 中好子数组的数目. 示例 1: 输入:A = [1,2,1,2,3], K = 2 输出:7 解释:恰好由 2 个不同整数组成的子数组:[1,2], [2,1], [1,2], [2,3], [1,2,1], [2,1,2], [1,2,1,2]. 示例 2: 输入:…

原题链接在这里:https://leetcode.com/problems/maximum-size-subarray-sum-equals-k/ 题目: Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Example 1: Given nums = [1, -1, 5, -2,…

原题链接在这里:https://leetcode.com/problems/maximum-size-subarray-sum-equals-k/ 题目: Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Note:The sum of the entire nums array…