CODEWITHSUNDEEP
javaloopsconditional-statements
CoopersInc
CoopersInc

Reputation: 55

Java Conditions Confusion? (Beginner)

The aim of this program is to make a Rock Paper Scissors game. I have succeeded in making it however I can not get it to loop no matter what I try. I tried:

while (index = 0)
while (index < gamesCount)

However, while my index is 0 and my condition says while (index != 0), it seems to be the only condition that runs the program but it will not loop regardless. How can I get my game to loop? 

import java.util.Scanner;
import java.util.Random;
public class RockPaperScissors {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        Random randomGen = new Random();
        //Variables
        String player1;
        int cpu;
        int start = 1;
        int end = 3;
        int index = 0;

        // 1 = Rock | 2 = Scissors | 3 = Paper
        //Code
        System.out.println("Welcome to Rock, Paper, Scissors!");
        while (index != 0) {
            System.out.print("Rock, Paper, or Scissors?: ");
            player1 = in.nextLine();
            cpu = randomGen.nextInt(3);
            System.out.println(cpu);

            if (player1.equals("Rock") && (cpu == 2)) {
                    System.out.println("You lose!");
            } else if (player1.equals("Rock") && (cpu == 1)) {
                    System.out.println("You win!");
            } else if (player1.equals("Rock") && (cpu == 0)) {
                System.out.println("Draw!");
            }

            // --------------------

            if (player1.equals("Scissors") && (cpu == 2)) {
                    System.out.println("Draw!");
            } else if (player1.equals("Scissors") && (cpu == 1)) {
                    System.out.println("You win!");
            } else if (player1.equals("Scissors") && (cpu == 0)) {
                    System.out.println("You lose!");
            }

            //---------------------

            if (player1.equals("Paper") && (cpu == 2)) {
                    System.out.println("You lose!");
            } else if (player1.equals("Paper") && (cpu == 1)) {
                    System.out.println("You win!");
            } else if (player1.equals("Paper") && (cpu == 0)) {
                    System.out.println("Draw!");
            }
        }
    }
}

Upvotes: 0

Views: 85

Answers (3)

John
John

Reputation: 376

You have your index variable set to 0. The condition of the while loop is saying, if index does not equal 0, execute the code in the loop. Since your index equals 0, the instructions in the loop will not be executed. Also, you will need to update the index variable in the loop so that if the condition you are looking for is met, the code will stop looping. ie:

int gamesPlayed = 0;
int gamesRequested = 3; // or get this from the user

while (gamesPlayed < gamesRequested){
    String player1Choice = in.nextLine();
    if(!"".equals(player1)){
    // your code
        gamesPlayed++;
    } else {
        System.out.print("Rock, Paper, or Scissors?: ");
    }
}

Upvotes: 1

Chronicler
Chronicler

Reputation: 59

Your index variable is set to a value of 0. Your while loop says

while (index != 0);

Which means, while the index isn't 0, run my code. The problem is your code will never run then because your index value is always 0. Try changing it to another value (say 5 for example), and it should work now.

:)

Upvotes: 1

Stultuske
Stultuske

Reputation: 9437

Two mistakes:

while (index != 0);

this is the entire loop. it ends either at the end of the { } block (which you don't have), or at the first ; which is immediately after the statement.

Correct this, though, and it still won't loop:

int index = 0;

        // 1 = Rock | 2 = Scissors | 3 = Paper



        //Code
        System.out.println("Welcome to Rock, Paper, Scissors!");
        while (index != 0);

index = 0, so (index != 0) will never return true.

Upvotes: 1

Related Questions