Sorting algorithms in different languages

bubblesort.c

#include <stdio.h>
#include <time.h>
#include <stdlib.h>

#define ARR_LEN 100

void swap(int *a, int *b)
{
	int temp = *a;
	*a = *b;
	*b = temp;
}

void bubblesort(int *arr, int len){
	int top = len-1;
	int j, newtop;

	while(top > 0){
		newtop = 0;
		for(j=0;j<top;j++){
			if(arr[j] > arr[j+1]){
				swap(&arr[j], &arr[j+1]);
				newtop = j+1;
			}
		}
		top = newtop;
	}
}


int main(int argc, char const *argv[])
{
	// const int len = 8;
	// int arr[] = {8,1,5,6,3,4,2,7};
	int arr[ARR_LEN];

	int i;
	srand(time(NULL));
	for(i=0;i<ARR_LEN;i++)
		arr[i] = rand()%100;


	for(i=0;i<ARR_LEN;i++)
		printf("%d ", arr[i]);
	printf("\n");

	bubblesort(arr, ARR_LEN);

	for(i=0;i<ARR_LEN;i++)
		printf("%d ", arr[i]);
	printf("\n");

	return 0;
}

quicksort.c

#include<stdio.h>
#include<stdlib.h>

void swap(int *a, int *b)
{
	// *a = *a ^ *b;
	// *b = *a ^ *b;
	// *a = *a ^ *b;

	int temp = *a;
	*a = *b;
	*b = temp;
}

void quicksort(int *arr, int start, int end)
{
	if(end-start<=0)
	{
		return;
	}

	int P = start;
	int L = start+1;
	int R = end;

	while(L <= R)
	{
		while(arr[L] < arr[P] && L <= end) //a bug? L<=end should be BEFORE element comparison?
		{
			L++;
		}
		if(arr[R] >= arr[P])
		{
			R--;
		}

		else
		{
			if(L<=R)
			{
				swap(&arr[L],&arr[R]);
			}
		}
	}
	//jumpover happened, swapping R and P and dividing
	swap(&arr[R],&arr[P]);

	quicksort(arr,start,R-1);
	quicksort(arr,R+1,end);
}

int main(int argc, char const *argv[])
{
	int n, i;
	int *arr;
	printf("%s\n", "Array size: ");
	scanf("%d", &n);

	arr = malloc(n * sizeof(int));

	printf("Enter the elements to be sorted\n");
	for(i = 0; i < n; i++)
		scanf("%d", &arr[i]);

	quicksort(arr, 0, n-1);

	for(i=0;i<n;i++)
		printf("%d,", arr[i]);
	printf("\n");

	return 0;
}