From 67e2e983115295aa75a62382264dbb6cff22592f Mon Sep 17 00:00:00 2001
From: Libin Yang <szuyanglb@outlook.com>
Date: Sun, 5 May 2019 15:23:58 +0800
Subject: [PATCH] Fix bug and format code in QuickSort.c

---
 sorting/QuickSort.c | 118 ++++++++++++++++++++++----------------------
 1 file changed, 60 insertions(+), 58 deletions(-)

diff --git a/sorting/QuickSort.c b/sorting/QuickSort.c
index 09cea80e..b69f8aec 100644
--- a/sorting/QuickSort.c
+++ b/sorting/QuickSort.c
@@ -1,100 +1,102 @@
 #include <stdio.h>
+#include <stdlib.h>
 
 /*Displays the array, passed to this method*/
+void display(int arr[], int n)
+{
 
-void display(int arr[], int n){
-
-	int i;
-	for(i = 0; i < n; i++){
-		printf("%d ", arr[i]);
-	}
-
-	printf("\n");
+    int i;
+    for (i = 0; i < n; i++)
+    {
+        printf("%d ", arr[i]);
+    }
 
+    printf("\n");
 }
 
 /*Swap function to swap two values*/
-void swap(int *first, int *second){
+void swap(int *first, int *second)
+{
 
-	int temp = *first;
-	*first = *second;
-	*second = temp;
-	
+    int temp = *first;
+    *first = *second;
+    *second = temp;
 }
 
-
 /*Partition method which selects a pivot
   and places each element which is less than the pivot value to its left
   and the elements greater than the pivot value to its right
-
   arr[] --- array to be partitioned
   lower --- lower index 
   upper --- upper index
 */
-int partition(int arr[], int lower, int upper){
+int partition(int arr[], int lower, int upper)
+{
 
-	int i = (lower  - 1);
+    int i = (lower - 1);
 
-	int pivot = arr[upper];	// Selects last element as the pivot value
+    int pivot = arr[upper]; // Selects last element as the pivot value
 
-	int j ;	
-	for(j = lower; j < upper ; j++){
+    int j;
+    for (j = lower; j < upper; j++)
+    {
 
-		if(arr[j] <= pivot){ // if current element is smaller than the pivot
+        if (arr[j] <= pivot)
+        { // if current element is smaller than the pivot
 
-			i++; // increment the index of smaller element
-			swap(&arr[i], &arr[j]);
-		}
-	}
+            i++; // increment the index of smaller element
+            swap(&arr[i], &arr[j]);
+        }
+    }
 
-	swap(&arr[i + 1] , &arr[upper]); // places the last element i.e, the pivot to its correct position
-   
-	return (i + 1); 
+    swap(&arr[i + 1], &arr[upper]); // places the last element i.e, the pivot to its correct position
+
+    return (i + 1);
 }
 
-
 /*This is where the sorting of the array takes place
 	arr[] --- Array to be sorted
 	lower --- Starting index
 	upper --- Ending index
 */
-void quickSort(int arr[], int lower,  int upper){
+void quickSort(int arr[], int lower, int upper)
+{
 
-	if(upper > lower){
+    if (upper > lower)
+    {
 
-		// partitioning index is returned by the partition method , partition element is at its correct poition
+        // partitioning index is returned by the partition method , partition element is at its correct poition
 
-		int partitionIndex = partition(arr, lower, upper); 
+        int partitionIndex = partition(arr, lower, upper);
 
-
-		// Sorting elements before and after the partition index
-		quickSort(arr, lower, partitionIndex - 1);
-		quickSort(arr, partitionIndex + 1, upper);
-	}
+        // Sorting elements before and after the partition index
+        quickSort(arr, lower, partitionIndex - 1);
+        quickSort(arr, partitionIndex + 1, upper);
+    }
 }
 
+int main()
+{
 
-int main(){
+    int n;
+    printf("Enter size of array:\n");
+    scanf("%d", &n); // E.g. 8
 
+    printf("Enter the elements of the array\n");
+    int i;
+    int *arr = (int *)malloc(sizeof(int) * n);
+    for (i = 0; i < n; i++)
+    {
+        scanf("%d", &arr[i]);
+    }
 
-	int n;
-	printf("Enter size of array:\n");
-	scanf("%d", &n); // E.g. 8
+    printf("Original array: ");
+    display(arr, n); // Original array : 10 11 9 8 4 7 3 8
 
-	printf("Enter the elements of the array\n");
-	int i;
-	int arr[n];
-	for(i = 0; i < n; i++){
-		scanf("%d", &arr[i] ); 
-	}
+    quickSort(arr, 0, n - 1);
 
-	printf("Original array: "); 
-	display(arr, n);       			// Original array : 10 11 9 8 4 7 3 8
-
-	quickSort(arr, 0, n-1);
-
-	printf("Sorted array: "); 
-	display(arr, n);				// Sorted array : 3 4 7 8 8 9 10 11
-
-	return 0;
-}
\ No newline at end of file
+    printf("Sorted array: ");
+    display(arr, n); // Sorted array : 3 4 7 8 8 9 10 11
+    getchar();
+    return 0;
+}