Stacks

#include<stdio.h>
#include<conio.h>
void push(int *array,int x,int *top)
{
*(array+*top)=x;
*top=*top+1;
}
int pop(int *array,int *top)
{
int x=*(array+*top-1);
*top=*top-1;
return x;
}
void peek(int *array,int *top)
{
if(*top-1<0)
printf("Stack Empty");
else
printf("%d",*(array+*top-1));
}
void display(int *array,int *top)
{
int i;
for(i=0;i<=*top-1;i++)
printf("%d\t",*(array+i));
}
void main()
{
int size,*top=0,*array,ch,l=0,x;
clrscr();
printf("Enter the size of array");
scanf("%d",&size);
array=(int*)malloc(2*size);
do
{
printf("Enter 1.Push 2.Pop 3.Peek 4.Display :");
scanf("%d",&ch);
switch(ch)
{
case 1:if(*top<size)
	{
	printf("Enter the element to insert : ");
	scanf("%d",&x) ;
	push(array,x,top);
	}
	else
	{
	printf("Stack Full");
	}
	break;
case 2:if(*top-1<0)
	printf("Stack Empty");
	else
	{
	x=pop(array,top);
	printf("Element popped out is %d",x);
	}
	break;
case 3:peek(array,top);
	break;
case 4:display(array,top);
	break;
case 5:l=1;
	break;
default:printf("Invalid Choice");
}
}while(l==0);
getch();
}