LeetCode: 39. Combination Sum

Problem: 39. Combination Sum

Link: https://leetcode.com/problems/combination-sum/

Algorithm: https://www.youtube.com/watch?v=irFtGMLbf-s

Difficulty: Medium

Description:

Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the candidate numbers sums to target.

The same repeated number may be chosen from candidates unlimited number of times.

Note:

• All numbers (including target) will be positive integers.
• The solution set must not contain duplicate combinations.

Example 1:

Input: candidates = [2,3,6,7], target = 7,
A solution set is:

[[7],[2,2,3] ]

Example 2:

Input: candidates = [2,3,5], target = 8,
Output:

[[2,2,2,2],[2,3,3],[3,5] ]

Solution: 

Language: Swift

Runtime: 28ms
Memory: 18.8MB