C language: quick sorting of sequential storage structure

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define MAXSIZE 10
void initArr(int arr[] , int length);
void showArr(int arr[] , int length);
void swap(int arr[] , int i , int j);
void quickSort2(int arr[] , int left , int right);
int main()
{
    
	srand((unsigned int)time(NULL));
	int arr[MAXSIZE];
	printf("========== The sequence before sorting =============\n");
	initArr(arr,MAXSIZE);
	showArr(arr,MAXSIZE);
	printf("========== Quick sort sequence in the form of single linked list =============\n");
	quickSort2(arr,0,MAXSIZE-1);
	showArr(arr,MAXSIZE);
	system("pause");
	return 0;
} 
void initArr(int arr[] , int length)
{
    
	for(int i = 0 ; i < length ; i++){
    
		arr[i] = rand()%20;
	}
}
void showArr(int arr[] , int length)
{
    
	for(int i = 0 ; i < length ; i++){
    
		printf("%4d",arr[i]);
	}
	printf("\n");
}
void swap(int arr[] , int i , int j)
{
    
	int temp = arr[i];
	arr[i] = arr[j];
	arr[j] = temp;
}
void quickSort2(int arr[] , int left , int right)
{
    
	// Quick sorting of sequential storage structure 
	if(left>=right){
    
		return;
	}
	int pivot = arr[left];
	int i = left+1;
	int j = left+1;
	while(j<=right){
    
		if(arr[j] < pivot){
    
// int temp = arr[i];
// arr[i] = arr[j];
// arr[j] = temp;
			swap(arr,i,j);
			i++;
		}
		j++;
	}
// int temp1 = arr[left];;
// arr[left] = arr[i-1];
// arr[i-1] = temp1;
	swap(arr,left,i-1);
	quickSort2(arr,left,i-1);
	quickSort2(arr,i,right);
}