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Thread: A variable that never change.

  1. #1
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    Question A variable that never change.

    Hi.

    I have an issue with my code:
    public class BuildBridge {
     
    	public static void main(String[] args) {
     
    		BuildBridge cartas = new BuildBridge();
     
    		int res = cartas.howManyCards(1,1);
     
    		System.out.print(res);
     
     
    	}
     
    	public int howManyCards(int d, int l) {
     
    		int results = 0;
    		double middle = l/2;
    		double increment = 0.0;
     
    		while (middle + increment < d) {
     
     
    			++results;
    			increment += middle / results; //
     
     
    		} 
     
    		return results;
    	}
     
    }

    The "increment" and "middle" variables are always zero, never change, even "middle" after the asignation "= l / 2". Only the variable "results" change when the while loop comes.

    Hope you can help, me.

    Thanks, have a nice day.


    Eclipse Standard/SDK

    Version: Kepler Release
    Build id: 20130614-0229
    Last edited by helloworld922; August 14th, 2013 at 01:01 PM. Reason: please use [code] tags


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    Default Re: A variable that never change.

    When posting code, please use the highlight tags to preserve formatting. You can edit your post and add them now.

    Have you stepped through this with a debugger, or at least added print statements, to figure out what's going on? When exactly does the code execution differ from what you expect?
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    Super Moderator helloworld922's Avatar
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    Default Re: A variable that never change.

    You're relying on integer math to calculate middle. You need to be using floating point math.

    The easiest way is to add a decimal to the 2.

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    Default

    Quote Originally Posted by helloworld922 View Post
    You're relying on integer math to calculate middle. You need to be using floating point math.

    The easiest way is to add a decimal to the 2.
    Thank you !!! that was the problem.

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