// Online C compiler to run C program online
#include <stdio.h>
#include<conio.h>
#include<stdlib.h>
#define MAX 5

int a[MAX] ,top=-1;
void push();
void pop();
void display();

int main() {
int ch;
printf("1. Push or insert\n");
printf("2. Pop or delete\n");
printf("3. display \n");
printf("4. exit\n");
// Write C code here
while(1){
    printf("\n enter choice");
    scanf("%d",&ch);
    switch(ch){
        case 1:
        {
            push();
            break;
        }
          case 2 :
        {
            pop();
            break;
        }
        
          case 3 :
        {
            display();
            break;
        }  case 4 :
        {
            exit(0);
          
        }
        default :{
            printf("invalid input");
        }
        
        
    }
    getch();
    return 0;
}

void push(){
    int data , input;
    if(top==MAX-1){
        printf("overflow");
    }
    else {
          printf("\n enter element");
           scanf("%d",&data);
           top++;
           a[top]=data;
    }
}
  
void pop(){
    
    if(top==-1){
         printf("underflow");
    }
    else{
         printf("Popped elemnt%d", a[top]);
         top--;
    }
    
    
}

void display(){
    int i;
    if(top>=0){
        printf("elements");
        for(i=top;i>=0;i--){
            printf("\n%d",a[i]);
        }
    }
    else{
        printf("empty stack");
    }
}