Implements Stack ADT

import java.io.*;
 class Stack 
{
 int s[]=new int[7];
 int t=-1;
 void push(int x)
 {
  if(t==6)
  {
   System.out.println("stack is full");
   return;
  }
   s[++t]=x;
 }
 void pop()
 {
  if(t==-1)
  {
   System.out.println("stack is empty");
  }
  else
  {
   System.out.println("element deleted from stack is"+s[t--]);
  }
 }
 void display()
 {
  
  if(t==-1)
  {
   System.out.println("stack is empty");
  }
  else
  {
   for(int i=0;i<=t;i++)
    System.out.println(s[i]);
  }
 }
}
class Stack1
{
 public static void main(String[] args)throws IOException 
 {
  BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
  Stack y=new Stack();
   System.out.println("Menu");
     System.out.println("1.push");
     System.out.println("2.pop");
     System.out.println("3.display");
     System.out.println("4.exit");
  out:while(true)
        {
    System.out.println("enter your choice");
      int ch=Integer.parseInt(br.readLine());
   switch(ch)
   {
      case 1:
    {
       System.out.println("enter the value");
       int n=Integer.parseInt(br.readLine());
       y.push(n);
       break;
    }
    case 2:
    {
     y.pop();
     break;
    }
    case 3:
     y.display();
         break;
    case 4:break out;
   }
  }
 }
}