ASCII art, drawing an asterisks diamond within dots.

[ajknight7498]

Hi all, new to the forum here. Currently doing a first year in a Computing course and have started learning my first programming language which is Java. Currently onto my second group of assignments and have been instructed to create a program which will drawn a diamond based on the width of a square. The number entered must be an odd number which i have already done. Here is my code and il explain the problem below:

public class Main
{
    public static void main(String args[])
    {
        System.out.println("#Size Of Square:");
        int sizeofsquare = 7;
        int down = 2;
        int across = 1;
        int dots = 0;
        int btmacross = 1;
        int stars = sizeofsquare / 2;
        int starn = sizeofsquare / 2;

        if ( sizeofsquare < 0 ){
            System.out.print( "Sides of square must be positive" );

        }
        if ( sizeofsquare >= 0 ){

            if (sizeofsquare % 2 == 0) {

                System.out.print( "Size " );
                System.out.print( "(" );
                System.out.print( sizeofsquare );
                System.out.print(") invalid must be odd" );
            }

            if (sizeofsquare % 2 != 0) {

                while ( sizeofsquare <= 40 ){

                    while ( across < sizeofsquare ){

                        System.out.print("."); 

                        if ( across == stars ){
                            System.out.print("*");
                        }                 

                        across = across + 1;

                    }
                    while ( down < sizeofsquare ){

                        stars = stars - 1;
                        starn = starn + 1;

                        System.out.println();

                        while ( dots < sizeofsquare ){
                            if ( dots == stars ){

                                System.out.print("*");
                                dots = dots + 1;
                            }
                            if ( dots == starn ){
                                System.out.print("*");
                                dots = dots + 1;
                            }
                            if ( dots < sizeofsquare ){
                                System.out.print(".");
                            }
                            dots = dots + 1;
                        }
                        if ( down > sizeofsquare / 2){

                            stars = sizeofsquare / 2;
                            starn = sizeofsquare / 2;
                                
                            if ( dots == stars ){
                                System.out.print("*");
                                dots = dots + 1;
                            }
                            if ( dots == starn ){

                                System.out.print("*");
                                dots = dots + 1;
                            }

                            if (dots < sizeofsquare ){
                                System.out.print(".");
                            }
                            dots = dots + 1;
                        }

                        down = down + 1;
                        dots = 0;

                    }
                    while (down == sizeofsquare){

                        System.out.println();

                        while ( btmacross < sizeofsquare ) {
                            System.out.print(".");

                            if ( btmacross == sizeofsquare / 2 ){
                                System.out.print("*");
                            }

                            btmacross = btmacross + 1;

                        }

                        down = down + 1;
                    }
                }
            }
        }
    }
}

This code outputs:

#Size Of Square:
...*...
..*.*..
.*...*.
*.....*
..*.*..
..*.*..
...*...

however it obviously needs to be:

#Size Of Square:
...*...
..*.*..
.*...*.
*.....*
.*...*.
..*.*..
...*...

Thanks for any help :)

[Norm]

Your logic seems not to put out enough inside .s on some lines. How do you determine how many dots to put out on each line?
None on first
1 on 2nd
3 on 3rd
5 on 4th
then reduce the number for the rest back to none.

What algorithm are you using to determine how many inside dots to put out on each line?

[ajknight7498]

I'm confused, from the results shown my program is outputting enough "."s but isn't putting the *'s below the middle of the diamond in the right place due to the starn and stars variables being the same. They both need to increase/decrease like before but i can't get it to do that as i have to redeclare the variables as sizeofsquare / 2 instead of using that area to have them change e.g stars = stars - 1 or whatever.

[Norm]

What is your logic to determine how to format what is on a line? How does the line number relate to what is printed on each line?
What is your algorithm for determining what goes on each line?