题目: Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The same repeated number may be chosen from C unlimited number of times. Note: All numbers (including target) w…

题目: Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combination. Note: All numbers (including target) will be…

Combination Sum Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The same repeated number may be chosen from C unlimited number of times. Note: All numbers (includi…

题目 Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combination. Note: All numbers (including target) will be p…

题目描述 给定一个无重复的正整数数组 candidates 和一个正整数 target, 求所有和为 target 的 candidates 中数的组合中.其中相同数的不同顺序组合算做同一种组合,candidates 中的数可以重复使用. 算法一 首先想到的方法就是枚举所有的组合可能性,判断其和是否为target.枚举的方法可以使用递归,对candidates中每一个数,有“加入组合”和“不加入组合”两种选择,每一种选择又可以向后面元素的不同选择递归,直到candidate中最后一个元素.可以用…

题目 Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The same repeated number may be chosen from C unlimited number of times. Note: All numbers (including target) wi…

这是一道简单题,但是我做了很久,主要难度在读题和理解题上. 思路:给定一个数字,返回这个数字报数数列.我们可以通过从1开始,不断扩展到n的数列.数列的值为前一个数列的count+num,所以我们不断叠加来完成. class Solution: def countAndSay(self, n: int) -> str: # 第一个值直接赋予 pre_num = " for i in range(1,n): # 用next_num 记录当前序列,num为前一个序列的第一个值 next_num,…

思路:先对数据进行排序(看评论给的测试数据好像都是有序数组了,但题目里没有给出这个条件),然后回溯加剪枝即可. class Solution { public: ; vector<vector<int>> ans; void search(int pos, vector<int>& candidates, int target, vector<int>& res, int sums){ if(sums == target){ ans.push…

1. 原题链接 https://leetcode.com/problems/combination-sum-ii/description/ 2. 题目要求 给定一个整型数组candidates[ ]和目标值target,找出数组中累加之后等于target的所有元素组合 注意:(1)每个可能的答案中,数组中的每一个元素只能使用一次:(2)数组存在重复元素:(3)数组中都是正整数:(4)不能存在重复解 3. 解题思路 这与第39题 Combination Sum 看起来很是类似,但一些细节要求完全不…

39. Combination Sum 1.Problem Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Example 1: Input: k = 3, n = 7 Output: [[1,2,…