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2020.2.6 494. Target Sum 我用的递归暴力解决的笨方法，本题有一种动态规划的好方法，但不能理解。待学习； 博客链接：https://www.cnblogs.com/qiang-wei/p/12271263.html 题目链接：https://leetcode.com/probl 阅读全文
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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 = 阅读全文
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You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose o 阅读全文
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Given a non-empty array of integers, return the k most frequent elements. Example 1: Input: nums = [1,1,1,2,2,3], k = 2 Output: [1,2] Example 2: Input 阅读全文