Java를 이용한 가위바위보 게임

package RockScissorPaper;
 
import java.util.Random;
import java.util.Scanner;
 
public class Rsp {
 
    public static void main(String[] args) {
        
        Random rand = new Random();
        Boolean asker = true;
        System.out.println("Welcome to Rock-Scissor-Paper Game!");
        
        while(asker){
            
            System.out.println("Choose // 1 : Rock , 2 : Scissor, 3 : paper");
            System.out.println("If you want to end the game,");
            System.out.println("just type other numbers except 1, 2 or 3");
            
            int rand_choose = (int)(Math.random() * 3 + 1);
            Scanner scan = new Scanner(System.in);
            int choose = scan.nextInt();
            
            if(1 != choose && 2 != choose && 3 != choose) {
                asker = false;
            } else if(choose == rand_choose) {
                System.out.println("Draw!");
            } else if(1 == choose && 2 == rand_choose || 2 == choose && 3 == rand_choose) {
                System.out.println("Oh...You Lose :<");
            } else {
                System.out.println("Congratulations! You Win! :)");
            }        
        
        }
        
        System.out.println("Game Over");
        
    }
 
}