C language: random number + Hill sort

#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 shellSort(int arr[] , int length);
int main()
{
    
	srand((unsigned int)time(NULL));
	int arr[MAXSIZE];
	printf("========== The sequence before sorting =============\n");
	initArr(arr,MAXSIZE);
	showArr(arr,MAXSIZE);
	printf("========== Hill sorted sequence =============\n");
	shellSort(arr,MAXSIZE);
	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 shellSort(int arr[] , int length)
{
    
	// Shell Sort 
	int h = 4;
	while(h>=1){
    
		for(int i = h ; i < length ; i++){
    
			for(int j = i ; j >= h && arr[j] < arr[j-h] ; j-=h){
    
				int temp = arr[j];
				arr[j] = arr[j-h];
				arr[j-h] = temp;
			}
		}
		h /= 2;
	}
}