# LeetCode 3Sum

Given an array *S* of *n* integers, are there elements *a*, *b*, *c* in *S* such that *a* + *b* + *c* = 0? Find all unique triplets in the array which gives the sum of zero.

**Note:**

- Elements in a triplet (
*a*,*b*,*c*) must be in non-descending order. (ie,*a*≤*b*≤*c*) - The solution set must not contain duplicate triplets.

For example, given array S = {-1 0 1 2 -1 -4},

A solution set is:

(-1, 0, 1)

(-1, -1, 2)

需要注意的是javascript的排序功能。Array.sort() function默认根据字母顺序排序，而非array value. 如果需要根据数值大小排序，需要另加排序function