From 793af0dc93112e90fe1320d0e7e443932455bcc7 Mon Sep 17 00:00:00 2001
From: ayusshrathore <ayusshrathore@gmail.com>
Date: Sat, 1 Oct 2022 22:33:14 +0530
Subject: [PATCH 1/2] Create QuickSort.java

---
 Sorting/QuickSort/QuickSort.java | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 Sorting/QuickSort/QuickSort.java

diff --git a/Sorting/QuickSort/QuickSort.java b/Sorting/QuickSort/QuickSort.java
new file mode 100644
index 0000000..e171aaf
--- /dev/null
+++ b/Sorting/QuickSort/QuickSort.java
@@ -0,0 +1,28 @@
+public class QuickSort {
+  public static void sort(int[] arr) {
+    sort(arr, 0, arr.length - 1);
+  }
+
+  private static void sort(int[] arr, int start, int end) {
+    if (start >= end)
+      return;
+    int boundary = partition(arr, start, end);
+    sort(arr, start, boundary - 1);
+    sort(arr, boundary + 1, end);
+  }
+
+  private static int partition(int[] arr, int start, int end) {
+    int pivot = arr[end];
+    int boundary = start - 1;
+    for (int i = start; i <= end; i++)
+      if (arr[i] <= pivot)
+        swap(arr, i, ++boundary);
+    return boundary;
+  }
+
+  private static void swap(int[] arr, int i, int j) {
+    int temp = arr[i];
+    arr[i] = arr[j];
+    arr[j] = temp;
+  }
+}

From 93d8e8e5267cf4b29614fdd65558c0a484b77574 Mon Sep 17 00:00:00 2001
From: ayusshrathore <ayusshrathore@gmail.com>
Date: Sun, 2 Oct 2022 10:40:48 +0530
Subject: [PATCH 2/2] Add explanation & complexities for QuickSort

---
 Sorting/QuickSort/QuickSort.java | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/Sorting/QuickSort/QuickSort.java b/Sorting/QuickSort/QuickSort.java
index e171aaf..5eea38e 100644
--- a/Sorting/QuickSort/QuickSort.java
+++ b/Sorting/QuickSort/QuickSort.java
@@ -1,3 +1,26 @@
+/**
+ * Explanation:
+ * 
+ * In this algorithm, we start by selecting the item which is known as a pivot,
+ * and then we re-arrange all the elements such that elements smaller than the
+ * pivot are on the left side & elements larger than the pivot appear on the
+ * right side of the pivot which is called partitioning, so we divide the array
+ * into two partitions that are separated by the pivot.
+ * 
+ * The same process is continued into the other two partitions, also in the case
+ * of reordering the items we did not worry about the right partition so we have
+ * narrowed down the scope of our work this is the reason why quick sort has
+ * logarithmic complexity because at every step we almost narrow down the size
+ * of our partition almost breaking them into half.
+ * 
+ * Space & Time Complexity:
+ * 
+ * Space -> O(log(n))
+ * 
+ * Time -> O(n log(n))
+ * 
+ */
+
 public class QuickSort {
   public static void sort(int[] arr) {
     sort(arr, 0, arr.length - 1);