Finding the frequency of the elements in the single linked list

frequency_linkedlist.c

//By luk0y
#include<stdio.h>
#include<stdlib.h>
struct node
	{
	int data;
	struct node *adr;
	};
void main()
{
	struct node *start=NULL,*nn,*ptr,*pttr;
	int x,y,n=0,l=0,i,j=0;
	int count=0;
	printf("Enter the nodes you want : \n");
scanf("%d",&y);
int k=y;
printf("Enter the values  :\n");
	while(y!=0)
	{
	    scanf("%d",&x);
		nn=(struct node*) malloc(sizeof(struct node));
		if(nn==NULL)
		{
			printf("no space");
		}
		else
		{
			n=n+1;
			if(start==NULL)
			{
				start=nn;
				nn->data=x;
				nn->adr=NULL;
			}
			else
			{
				ptr=start;
				while(ptr->adr!=NULL)
				{
					ptr=ptr->adr;
				}
				ptr->adr=nn;
				nn->data=x;
				nn->adr=NULL;
			}
		}
y--;
	}
	ptr=start;
	printf("Linked list : \n");
	while(ptr!=NULL)
	{
		printf("%d\n",ptr->data);
		ptr=ptr->adr;
	}
	printf("\n\n");
	for(i=1;i<n;i++)
	{
		ptr=start;
		pttr=ptr->adr;

		for(j=0;j<(n-i);j++)
		{
			if(ptr->data>pttr->data)
			{
				l=ptr->data;
				ptr->data=pttr->data;
				pttr->data=l;
			}
			ptr=pttr;
			pttr=pttr->adr;
		}
	}
	ptr=start;
	printf("Final : \n");
	x=ptr->data;
	while(ptr!=NULL)
	{
	    if(ptr->data==x){
		count=count+1;
		ptr=ptr->adr;
	    }
	    else
            {
        printf("Frequency of %d = %d\n",x,count);
        count=0;
        x=ptr->data;
            }
	}
printf("Frequency of %d = %d\n",x,count);
}