From 779016541c89e2214b13838f0b79f6e69b3d927d Mon Sep 17 00:00:00 2001
From: Mahdi Saffari <mmsaffari@gmail.com>
Date: Sat, 19 Jan 2019 11:45:34 +0330
Subject: [PATCH] QuickSort Added.

---
 Exercises and Samples/Program.cs     | 11 +++++++---
 Exercises and Samples/SortMethods.cs | 31 +++++++++++++++++++++++++++-
 2 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/Exercises and Samples/Program.cs b/Exercises and Samples/Program.cs
index 0baca74..7061ea5 100644
--- a/Exercises and Samples/Program.cs	
+++ b/Exercises and Samples/Program.cs	
@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 
 namespace Exercises_and_Samples {
 	class Program {
@@ -11,12 +12,16 @@ static void Main(string[] args) {
 			//int Number = Convert.ToInt32(Console.ReadLine());
 			//Console.WriteLine("Index of {0} in the List is {1}", Number, BinarySearch_Recursive(Number, List, 0, List.Length));
 
-			int[] List = new int[] { 10, 41, 15, 132, 102, 23, 265, 176, 90 ,10};
+			int[] List = new int[] { 10, 41, 15, 132, 102, 23, 265, 176, 90, 10 };
 			Console.WriteLine("UnSorted: [{0}]", string.Join(", ", List));
 			//List = SortMethods.InsertionSort(List);
 			//Console.WriteLine("Insertion Sorted: [{0}]", string.Join(", ", List));
-			List = SortMethods.MergeSort(List);
-			Console.WriteLine("Merge Sorted: [{0}]", string.Join(", ", List));
+			//List = SortMethods.MergeSort(List);
+			//Console.WriteLine("Merge Sorted: [{0}]", string.Join(", ", List));
+			List = SortMethods.QuickSort(List);
+			List = SortMethods.QuickSort(List);
+			List = SortMethods.QuickSort(List.Reverse().ToArray());
+			Console.WriteLine("Quick Sorted: [{0}]", string.Join(", ", List));
 
 
 			//for (int i = 0; i < List.Length; i++) {
diff --git a/Exercises and Samples/SortMethods.cs b/Exercises and Samples/SortMethods.cs
index 0277e76..437439f 100644
--- a/Exercises and Samples/SortMethods.cs	
+++ b/Exercises and Samples/SortMethods.cs	
@@ -16,7 +16,6 @@ public static T[] InsertionSort<T>(T[] input) where T : IComparable {
 			return result;
 		}
 
-
 		public static T[] MergeSort<T>(T[] input) where T : IComparable {
 			int n = input.Length;
 
@@ -47,6 +46,36 @@ public static T[] MergeSort<T>(T[] input) where T : IComparable {
 
 			return input;
 		}
+
+		public static T[] QuickSort<T>(T[] input) where T : IComparable {
+			T[] result = input.Clone() as T[];
+			QuickSort(result, 0, result.Length - 1);
+			return result;
+		}
+		private static void QuickSort<T>(T[] input, int low, int high) where T : IComparable {
+			if (low < high) {
+				int q = Partition(input, low, high);
+				if (q > 1) { QuickSort(input, low, q - 1); }
+				if (q + 1 < high) { QuickSort(input, q + 1, high); }
+			}
+		}
+		private static int Partition<T>(T[] input, int low, int high) where T : IComparable {
+			T x = input[low];
+			int i = low + 1;
+			int j = high;
+			do {
+				while (i <= high && input[i].CompareTo(x) < 0) { i++; }
+				while (j >= low && input[j].CompareTo(x) > 0) { j--; }
+				if (i < j) { Swap(ref input[i], ref input[j]); }
+			} while (i < j);
+			Swap(ref input[low], ref input[j]);
+			return j;
+		}
+		private static void Swap<T>(ref T v1, ref T v2) {
+			T temp = v1;
+			v1 = v2;
+			v2 = temp;
+		}
 	}