From 7e370027c3f9e1ee01c2694f2f64272b5b7aeb09 Mon Sep 17 00:00:00 2001
From: AJAY <74255983+ajayTemp@users.noreply.github.com>
Date: Sat, 21 Oct 2023 14:20:30 +0530
Subject: [PATCH] Create 3sum.cpp

---
 C++/3sum.cpp | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 C++/3sum.cpp

diff --git a/C++/3sum.cpp b/C++/3sum.cpp
new file mode 100644
index 0000000..37e20e4
--- /dev/null
+++ b/C++/3sum.cpp
@@ -0,0 +1,43 @@
+class Solution {
+public:
+    vector<vector<int> > threeSum(vector<int> &num) {
+
+        vector<vector<int> > res;
+
+        std::sort(num.begin(), num.end());
+
+        for (int i = 0; i < num.size(); i++) {
+
+            int target = -num[i];
+            int front = i + 1;
+            int back = num.size() - 1;
+
+            while (front < back) {
+
+                int sum = num[front] + num[back];
+
+                if (sum < target)
+                    front++;
+
+                else if (sum > target)
+                    back--;
+
+                else {
+                    vector<int> triplet = {num[i], num[front], num[back]};
+                    res.push_back(triplet);
+
+                    while (front < back && num[front] == triplet[1]) front++;
+
+                    while (front < back && num[back] == triplet[2]) back--;
+                }
+
+            }
+
+            while (i + 1 < num.size() && num[i + 1] == num[i])
+                i++;
+        }
+
+        return res;
+
+    }
+};