Thread: Display patterns using loops

Used nested loops that display following patterns

                *
               ***
              *****
               ***
                *

I only able to have this, after that stucked.

for (int i = 0; i < 5; i++) {
    for (int j = 0; j <= i * 2; j++) {
         System.out.print("*");
	}
         System.out.println();
	}

Can you post the program's current output to show what it does?

Describe the pattern of the output:
how many lines are printed?
what goes on each line?

Current output is

*
***
*****
*******
*********

Can you describe the pattern of the desired output:
how many lines are printed?
what goes on each line?
How does what is printed on a line relate to what line is being printed?

Thanks for your reply Norm, I actually want it to print a diamond.
I have solved it.

     for (int i = 1; i < 5; i += 2) {
			for (int j = 0; j < 4 - i / 2; j++)
			   System.out.print(" ");
 
			for (int j = 0; j < i; j++)
			  System.out.print("*");
 
			System.out.println();
		}
 
		for (int i = 5; i > 0; i -= 2) {
			for (int j = 0; j < 4 - i / 2; j++)
				System.out.print(" ");
 
			for (int j = 0; j < i; j++)
				System.out.print("*");
 
			System.out.println();
		}

want it to print a diamond.
I have solved it.

You could Wrap the post of the output in code tags to preserve the leading spaces so we can see its shape.

Glad you solved it.

Note: The code has too many "magic numbers". Can you change it so the number of lines to print is in a variable and then the contents of that variable is used to control the logic?
Then make it a method and execute it with different values.

You could Wrap the post of the output in code tags to preserve the leading spaces so we can see its shape.

This is the output

   * 
  * * 
 * * * 
  * * 
   *

What did you mean "magic numbers" ?

All the 5s and 4s should be replaced by variables. The 2 is ok because it is used to get half of a value and would never change.

Don't understand Did you mean it would be better if I assign a variable to 4 and 5 ?

Replace the numbers 4 and 5 with variables. Don't hard code numbers in the code.
Then write a method that takes the number of rows as its arg.
Call the method with different values for the number of rows.

I think you mean this ?

public class Example {
 
	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		System.out.print("Key in the row you want it to display: ");
		int k = input.nextInt();
		Example x = new Example();
		x.getPatternDisplay(k);
	}
 
	public void getPatternDisplay(int k) {
 
		for (int i = 1; i < k; i += 2) {
			for (int j = 0; j < k - i / 2; j++)
				System.out.print(" ");
			for (int j = 0; j < i; j++)
				System.out.print("*");
			System.out.println();
		}
 
		for (int i = k; i > 0; i -= 2) {
			for (int j = 0; j < k - i / 2; j++)
				System.out.print(" ");
			for (int j = 0; j < i; j++)
				System.out.print("*");
			System.out.println();
		}
	}
}

Yes, something like that. The variable name k is a bit obscure: k??? instead of nbrOfRows that describes what is in it.

Thanks, I will aware of the variables used next time