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Thread: Do While Loop

  1. #1
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    Default Do While Loop

    First of all, hey, Im a bit new to this board, and really needed help so thought it would be a good place to get some help.

    Okay this is what i'm trying to do,

    I want to create 50 random numbers assigned to different values, and tried using a do while loop for this.
    E.g.

    randomNumber1 = 34;
    randomNumber2 = 43;

    but without having to declare 50 numbers by hand, and rather have a loop to create it for me.

    Here is the small bit of code for it that I wrote up:

    int generateNum = 0;
    int currrentValue = 2;
     
    do {
          int randomNumber = (int)Math.round((Math.random() * 365) + 1); 
          }
     
    while (generateNum < 49) {
     
           int randomNumber.currentValue = (int)Math.round((Math.random() * 365) + 1);
     
                        currentValue++;
                        generagteNum++;
           }
    However upon compiling it gives the error message " ; expected " on the "while (generateNum < 39) {" line.



    Anyone that can help me out of it?


  2. #2
    Senile Half-Wit Freaky Chris's Avatar
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    Default Re: Do While Loop

    Thats a very wierd piece of code if i do say so myself. Have a read up on Arrays, they will show you the light

    Chris
    chris[at]javaprogrammingforums[dot]com

    Prifysgol Bangor University, North Wales

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    Default Re: Do While Loop

    Damn, didn't think about using an array. I think I should be able to do that quite easily. Thanks for the tip!

    And btw, any chance you can elaborate on the 'weird' piece of coding? I'm more or less a complete newbie so any help to improve my coding is greatly appreciated

  4. #4
    Senile Half-Wit Freaky Chris's Avatar
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    Default Re: Do While Loop

    What is randomNumber.currentValue? never seen anything like it
    chris[at]javaprogrammingforums[dot]com

    Prifysgol Bangor University, North Wales

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    Default Re: Do While Loop

    ... there should be a few compile errors in that code. do-while statements require a semi-colon after the while loop. Also, you're declaring two local variables with the same name (randomNumber). The int data type also doesn't have any sub-fields/methods, that's why it's a primitive data type in Java. Also, your do-while loop is generating a random number an infinite number of times without doing anything else. That will cause your program to hang, and also you really should do something each time a random number is generated.

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    Super Moderator Json's Avatar
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    Default Re: Do While Loop

    What you want to do is something like this.

    final int[] integers = new int[50]; // create the array to hold 50 primitive integers
    final Random random = new Random(); // create the random generator, can be found in java.util package
     
    // Loop 50 times and create a random number each time and assign it to the correct index in the array
    for(int index = 0; index < 50; ++index) {
        integers[index] = random.nextInt(); // generate number and store in the array
    }

    // Json

  7. The Following User Says Thank You to Json For This Useful Post:

    connex (December 7th, 2009)

  8. #7
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    Default Re: Do While Loop

    Quote Originally Posted by Freaky Chris View Post
    What is randomNumber.currentValue? never seen anything like it
    I was trying to increment the currentValue by one each time, e.g. 1, 2, 3, then append it to randomNumber so it generates random variables like:

    randomNumber1
    randomNumber2
    etc...

    I think that functionality is with PHP which is why I got confused to why it didn't work.

    And thanks Json, I already worked out a solution using arrays, which is similar to the solution you gave me. Thanks for the help though!

    If there is a way to set this as solved, now would be the time to do it

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