Program of Implentation of stack using arrays

/* Implentation of stack using arrays - STACK.C */
# include "stdio.h"
# include "conio.h"
# define SIZE 10
int arr[SIZE], top = -1, i ;
void push() ;
void pop() ;
void display() ;
void main()
{
int ch ;
clrscr() ;
do
{
printf("[1].PUSH [2].POP [3].Display [4].Exit") ;
printf("Enter your choice [1-4] : ") ;
scanf("%d", &ch) ;
switch(ch)
{
case 1 :
push() ;
break ;
case 2 :
pop() ;
break ;
case 3 :
display() ;
break ;
case 4 :
break ;
default :
printf("Invalid option") ;
getch() ;
}
}
while(ch != 4) ;
getch() ;
}

void push()
{
if(top == SIZE - 1)
{
printf("Stack is full (overflow)") ;
getch() ;
return ;
}
top++ ;
printf("Enter the element to PUSH : ") ;
scanf("%d", &arr[top]) ;
}

void pop()
{
if(top == -1)
{
printf("Stack is empty (underflow)") ;
getch() ;
return ;
}
printf("The POP element is : %d", arr[top]) ;
getch() ;
top-- ;
}

void display()
{
if(top == -1)
{
printf("Stack is empty (underflow)") ;
getch() ;
return ;
}
printf("The elements in stack are :TOP") ;
for(i = top ; i >= 0 ; i--)
printf(" -> %d", arr[i]) ;
printf("") ;
getch() ;
}