how to use qsort in c code example

Example 1: qsort in c

#include <stdlib.h>
int cmpfunc (const void * a, const void * b) {
   return ( *(int*)a - *(int*)b );
}

int main () {
//n is number of elements in arr(size f that arr)
   qsort(arr, n, sizeof(int), cmpfunc);
   }

Example 2: quick sort predefined function in c++

#include <cstdlib>

//declare compare
int compare(const void* a, const void* b)
{
	const int* x = (int*) a;
	const int* y = (int*) b;

	if (*x > *y)
		return 1;
	else if (*x < *y)
		return -1;

	return 0;
}

//fuction used
qsort(arr,num,sizeof(int),compare);