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Thread: Trying to get an "if" statement to work in a "for loop".

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    Default Trying to get an "if" statement to work in a "for loop".

    This isn't homework, it's a question in a textbook practice example that I can't seem to get right.
    I got it to work with 3 for loops, but I don't know how to get it to work with 2 for loops and a if statement.
    Can someone show me how to get the following :

     
    /* 
    *Write a nested for loop to display the following matrix: 
    *1 2 3 4
    *   1 2 3
    *      1 2
    *         1
    * basically they just increase by 2 spaces every iteration it seems like.
    */
     
     
    //this is as much of a layout of my code i can do
     
    for (int i = 1; i <= 4; i++) {
        for (int j = 1; j <= 5 - i; j++) { //i have a feeling the if statement should go after the 2nd for loop, but i can't get it to work.
            System.out.print(j + " ");
        }
        System.out.println();
    }


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    Default Re: Trying to get an "if" statement to work in a "for loop".

    Why do you need an if statement? You only need 2 loops. Outer loop controls the number of rows. For each row print x number of spaces then have the inner loop print the numbers.

    --- Update ---

    On reflection I assume they want you to use the if statement to decide if a space or a number should be printed.
    Improving the world one idiot at a time!

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    Default Re: Trying to get an "if" statement to work in a "for loop".

    I just assumed there needed to be an if statement because I couldn't get each row to increase by " " (2 spaces) each time. How would you increase it by 2 spaces each iteration then? normally this would just print 1 2 3 4 for each row and have 4 columns, but instead its decreasing by 1 number (which i did by j<=5-i) and also shifting to the right every iteration which i can't figure out how to do. Is there a way to do that with just 2 for loops?

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    Default Re: Trying to get an "if" statement to work in a "for loop".

    I got this to work using a place holder that would increment each iteration of the outer for-loop.

    ...
    Last edited by copeg; April 1st, 2013 at 11:10 PM. Reason: spoonfeeding

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    Default Re: Trying to get an "if" statement to work in a "for loop".

    @Mitch, this is a problem solving exercise - please refrain from spoonfeeding (for reasons why, please read The Problem with Spoon-feeding )

    @JAKATAK, try writing this out on paper. If you use nested loops, does one of the loop value account for the number of spaces or space offset?

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