From d1aa6319de73d8577687a6fb412b240acc1a8e35 Mon Sep 17 00:00:00 2001
From: pg8469 <43347426+pg8469@users.noreply.github.com>
Date: Thu, 31 Oct 2019 12:25:07 +0530
Subject: [PATCH] Create 3_way_quicksort.cpp

Better quicksort which works on duplicate data also.
---
 Sorting/QuickSort/C++/3_way_quicksort.cpp | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 Sorting/QuickSort/C++/3_way_quicksort.cpp

diff --git a/Sorting/QuickSort/C++/3_way_quicksort.cpp b/Sorting/QuickSort/C++/3_way_quicksort.cpp
new file mode 100644
index 00000000..8dc4a638
--- /dev/null
+++ b/Sorting/QuickSort/C++/3_way_quicksort.cpp
@@ -0,0 +1,20 @@
+#include<bits/stdc++.h>
+using namespace std;
+void swap(int* arr,int a,int b){
+	int temp=arr[a];
+	arr[a]=arr[b];
+	arr[b]=temp;
+}
+void qs(int* arr,int start,int end){
+	if(start>=end)
+		return;
+	int pivot=arr[start];
+	int first=start,last=end,mid=start+1;
+	while(mid<=last){
+		if(arr[mid]<pivot)	swap(arr,first++,mid++);
+		else if(arr[mid]>pivot)	swap(arr,mid,last--);
+		else	mid++;
+	}
+	qs(arr,start,first-1);
+	qs(arr,last+1,end);
+}