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Thread: Making Coin Toss for Football game

  1. #1
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    Default Making Coin Toss for Football game

    Hello, I am trying to construct a football simulator game, here is the code that I have so far:

    import java.util.Scanner;
    import java.util.Random;
     
    public class gamePlay{
     
    	public static int Downs = 0;
    	public static int Yards = 0;
    	public static String Coin = null;
    	public static String Choice = null;
    	public static String Toss = null;
    	public static String heads;
    	public static String tails;
    	public static String Heads;
    	public static String Tails;
    	public static String Yes;
    	public static String No;
    public static void main (String[]args){
     
    	Scanner keyboard = new Scanner(System.in);
     
    	System.out.println("Welcome to todays game, it's time for the coin toss.");
    	System.out.println("Please Pick Heads Or Tails By typing you answer.");
    	String HT = keyboard.nextLine();
    	switch(HT)
    	{
    	case "Heads":
    	case "heads":
    		Choice = heads;
    		//TODO Make Answer Random
    		coinToss();
    		break;
    	case "Tails":
    	case "tails":
    		Choice = tails;
    		//TODO Make Answer Random
    		coinToss();
    		break;
    		}
    		//TODO Test The Above
     
    	if(Coin == Heads && (Choice == heads))
    	{
    		System.out.println("You have won the coin toss!");
    		Toss = Yes;
     
    	}else if (Coin == Heads && (Choice == tails)){
    		System.out.println("You have lost the coin toss...");
    		Toss = No;
    	}
    	if(Coin == Tails && (Choice == tails))
    	{	
    		System.out.println("You have won the coin toss!");
    		Toss = Yes;
    	}else if (Coin == Tails && (Choice == heads)){
    		System.out.println("You have lost the coin toss...");
    		Toss = No;
    	}
    	if(Toss == Yes)
    	{
    	//Insert Something here
    	}else if(Toss == No)
    	{
    	//Insert Something here
    	}
    }
     
    public static void coinToss()
    {
    Random coin = new Random();
    int coinRand = coin.nextInt(2);
     
    if (coinRand == 0)
    {
    	System.out.println("The Result was Heads....");
    	Coin = Heads;
    }else{
    System.out.println("The Result was Tails....");
    Coin = Tails;
    }
     
     
     
    	}
     
    }
    My issue is when I run it, it prints "You have won the coin toss!" twice, no matter what the outcome is, could you explain to me what I am doing wrong?


  2. #2
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    Default Re: Making Coin Toss for Football game

    This is a shot in the dark, but I would have used the toss = Math.random(). Then if between 0 and .5 would be equal to heads or tails. Then .6 to 1.0 will be
    equal to the other.

    I would then have a variable call.

    if(call == toss)
    {
       System.out.println("you won the toss");
    }
     
    else
    {
       System.out.println("You lost the toss");
    }

    you are printing that out twice because any expression that evaluates to false will print that line, and in both those cases it does.

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    Default Re: Making Coin Toss for Football game

    Ok, how would I make it only have 1 false and 1 true statement? Would it just be a single if-else statement instead?

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    Default Re: Making Coin Toss for Football game

    I would try something like this:

     
    public static String CoinToss(String toss)
    {
       double call;
       double toss2;
       toss2 = Double.parseDouble(toss);
       String output;
     
      call = Math.random();
     
       if(call == toss)
       {
           output = "You won the coin toss";
        }
     
       else
        {
           output = "You lost the coin toss";
         }
       return output;
    }

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    Default Re: Making Coin Toss for Football game

    it should be (call == toss2) sorry

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    Default Re: Making Coin Toss for Football game

    Your message prints twice because you have (as you frame it) 4 separate outcomes (choose heads / coin heads, choose heads / coin tails, choose tails / coin heads, choose tails / coin tails), and you have *two* if-else statements like
    if (1)
    {}
    else if (2)
    {}
    if (3)
    {}
    else if (4)
    {}
    where you should have
    if (1)
    else if (2)
    else if (3)
    else if (4)
    so that only one condition matches.
    That would stop your message appearing twice, but there's another fault in your code: you're assigning
    		Choice = heads;
    but 'heads' is a String reference that has never been assigned - it is null, as is 'tails'

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