From 7e74eced2ead9fde8d02bde895a3c0d5f579253f Mon Sep 17 00:00:00 2001
From: MITHILESH <mkumar199861@gmail.com>
Date: Thu, 1 Oct 2020 12:49:46 +0530
Subject: [PATCH] Create 3-Sum.cpp
---
cpp/3-Sum.cpp | 47 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 47 insertions(+)
create mode 100644 cpp/3-Sum.cpp
diff --git a/cpp/3-Sum.cpp b/cpp/3-Sum.cpp
new file mode 100644
index 0000000000..1c99b34de1
--- /dev/null
+++ b/cpp/3-Sum.cpp
@@ -0,0 +1,47 @@
+class Solution {
+public:
+ vector<vector<int>> threeSum(vector<int>& nums) {
+
+ //
+ vector<vector<int>> res;
+ //sort
+ sort(nums.begin(),nums.end());
+
+ for(unsigned int i = 0; i < nums.size();i++){
+ // initialize left and right
+ //to handle duplicates
+ if(i > 0 && nums[i]==nums[i-1])
+ continue;
+ int l = i + 1;
+ int r = nums.size() - 1;
+ int x = nums[i];
+
+ while (l < r)
+ {
+ if (x + nums[l] + nums[r] == 0) {
+ res.push_back(vector<int>{x,nums[l],nums[r]});
+ //to handle duplicates
+ while (l<r && nums[l] == nums[l+1])
+ l++;
+ // to handle duplicates
+ while (l<r && nums[r] == nums[r-1])
+ r--;
+ l++;
+ r--;
+ //break;
+ }
+ // If sum of three elements is less
+ // than zero then increment in left
+ else if (x + nums[l] + nums[r] < 0)
+ l++;
+
+ // if sum is greater than zero than
+ // decrement in right side
+ else
+ r--;
+ }
+
+ }
+ return res;
+ }
+};