first.java

import java.util.*;
public class first {
    public static void main(String[] args){
       System.out.println("hello world");
        System.out.println("*");
        Scanner sc =new Scanner(System.in);//input
        String name = sc.next();//for taking input
        System.out.println(name);

        //conditional statements

        int age=sc.nextInt();
        if (age>=18) 
        {
            System.out.println("adult");  
        }
        else{
            System.out.println("non adult");
        }
        int num=sc.nextInt();
        if(num%2==0){
            System.out.println("even");
        }else{
            System.out.println("odd");
        }
        //switch case
        
        int button=sc.nextInt();
        switch(button){
            case 1:System.out.println("Hello");
            break;
            case 2:System.out.println("Namaste");
            break;
            case 3:System.out.println("Bonjour");
            break;
            default:System.out.println("invalid button");
        }
    }
}