Lintcode17 Subsets solution 题解

【题目描述】

Given a set of distinct integers, return all possible subsets.

Notice:Elements in a subset must be in non-descending order;The solution set must not contain duplicate subsets.

给定一个含不同整数的集合，返回其所有的子集

注意：子集中的元素排列必须是非降序的，解集必须不包含重复的子集

【题目链接】

http://www.lintcode.com/en/problem/subsets/

【题目解析】

子集类问题类似Combination，以输入数组[1, 2, 3]分析，根据题意，最终返回结果中子集类的元素应该按照升序排列，故首先需要对原数组进行排序。题目的第二点要求是子集不能重复，至此原题即转化为数学中的组合问题。我们首先尝试使用 DFS 进行求解，大致步骤如下：

[1] -> [1, 2] -> [1, 2, 3]

[2] -> [2, 3]

[3]

将上述过程转化为代码即为对数组遍历，每一轮都保存之前的结果并将其依次加入到最终返回结果中。

【答案链接】

http://www.jiuzhang.com/solution/subsets/

时间： 2024-08-06 11:37:56

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