Java program to play Rock, Paper and Scissors with computer.

import java.lang.*;
import java.util.Scanner;
import java.util.Random;

public class RPS{
    
    public int user_score =0 , comp_score = 0;
    public String user_choice, comp_choice;
    Random ran;
    Scanner scan;

    public RPS(){
        ran = new Random();
        scan = new Scanner(System.in);
    }

    public void userTurn(){
        System.out.println("\n[1] Rock , [2] Paper , [3] Scissors");
        System.out.print("Choice > ");
        user_choice = whatIsIt(scan.nextInt() - 1);
    }

    public void machineTurn(){
        comp_choice = whatIsIt(ran.nextInt(3) + 1);
    }

    public String whatIsIt(int a){
        if(a==0){
            return "Rock";
        }
        if(a==1){
            return "Paper";
        }
        return "Scissors";
    }

    public String whoKilled(){
        if(user_choice!= comp_choice){
            if(user_choice== "Rock"){
                if(comp_choice == "Paper"){
                    comp_score++;
                    return "comp";
                }
                else{
                    user_score++;
                    return "user";
                }
            }
            if(user_choice== "Paper"){
                if(comp_choice == "Rock"){
                    user_score++;
                    return "user";
                }
                else{
                    comp_score++;
                    return "comp";
                }
            }
            if(user_choice== "Scissors"){
                if(comp_choice == "Rock"){
                    comp_score++;
                    return "comp";
                }
                else{
                    user_score++;
                    return "user";
                }
            }                
        }
        return "Draw";
    }

    public String whoWon(){
        scan.close();
        if(user_score>comp_score){
            return "user";
        }
        else{
            return "comp";
        }
    }
}

class Controller{
    public static void main(String[] args) {
        RPS rpc = new RPS();
        int times=5;
        String who;

        System.out.println("#####  Rock  Paper  Scissors  #####");

        while(times>0){
            rpc.userTurn();
            rpc.machineTurn();
            who = rpc.whoKilled();
            System.out.println("\nMachine Choose : "+rpc.comp_choice);
            switch(who){
                case "user" -> {
                    times--;
                    System.out.println("You killed Computer !!");
                }
                case "comp" -> {
                    times--;
                    // System.out.println("Machine Choose : "+rpc.comp_choice);
                    System.out.println("computer killed you !!");
                }
                default -> System.out.println("\nIts a Draw.");
            }
        }
        System.out.println("\nScore: [ You -> "+rpc.user_score+" ] [ Computer -> "+rpc.comp_score+" ]");
        if(rpc.whoWon() == "user"){
            System.out.println("\nCongratulation!! You have won!!\n");
        }
        else{
            System.out.println("\nComputer defeated you!!\n");
        }
    }
}