Merge pull request #1 from kartiktom/kartiktom-patch-1

Create 3sum.txt

Author: kartiktom

Array/leetcode 3sum/3sum.txt

@@ -0,0 +1,22 @@
+Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero.
+
+Notice that the solution set must not contain duplicate triplets.
+
+Example 1:
+
+Input: nums = [-1,0,1,2,-1,-4]
+Output: [[-1,-1,2],[-1,0,1]]
+Example 2:
+
+Input: nums = []
+Output: []
+Example 3:
+
+Input: nums = [0]
+Output: []
+ 
+
+Constraints:
+
+0 <= nums.length <= 3000
+-105 <= nums[i] <= 105