#include<stdio.h>

#include<stdlib.h>

#define Size 4

int Top=-1, inp_array[Size]; void Push(); void Pop(); void show();

int main() { int choice;

while(1)	
{
	printf("\nOperations performed by Stack");
	printf("\n1.Push the element\n2.Pop the element\n3.Show\n4.End");
	printf("\n\nEnter the choice:");
	scanf("%d",&choice);
	
	switch(choice)
	{
		case 1: Push();
				break;
		case 2: Pop();
				break;
		case 3: show();
				break;
		case 4: exit(0);
		
		default: printf("\nInvalid choice!!");
	}
}

}

void Push() { int x;

if(Top==Size-1)
{
	printf("\nOverflow!!");
}
else
{
	printf("\nEnter element to be inserted to the stack:");
	scanf("%d",&x);
	Top=Top+1;
	inp_array[Top]=x;
}

}

void Pop() { if(Top==-1) { printf("\nUnderflow!!"); } else { printf("\nPopped element: %d",inp_array[Top]); Top=Top-1; } }

void show() {

if(Top==-1)
{
	printf("\nUnderflow!!");
}
else
{
	printf("\nElements present in the stack: \n");
	for(int i=Top;i>=0;--i)
		printf("%d\n",inp_array[i]);
}

}