/*
This program is to demostrate how methods can be built in Java.
Here, we build a method that accepts an integer that represents a certain mnumber of lines.
If the number of lines is even, we print an error message and exit.
If the number of lines is odd, we print a triangular arrangement of *'s with those many lines.
For example, if t/he number of lines is 7, we print
*
* *
* * *
* * * *
* * *
* *
*
This is a method with a void return type, as it only prints things and doesn't return any value.
*/
import java.util.Scanner;
class Method
{
	static void printStar(int lines) // declared static because we're calling the method without instantiating a class.
	{			// accepts 1 integer parameter, the number of lines
		if(lines % 2 == 0)
		{	// print error message if even
			System.out.println("Even number of lines. Can't print.");
			return;
		}
		// will get here only if lines is odd

		// This prints the top half of the triangle.
		for (int i=0;i<=lines/2;i++)
		{
			for(int j=0;j<=i;j++)
				System.out.print("* ");
			System.out.println("");
		}

		// This prints the bottom half of the triangle
		for (int k = lines/2+1; k<lines;k++)
		{
			for(int j=lines-k;j>0;j--)
				System.out.print("* ");
			System.out.println("");
		}
	}
	
	// main method. Can't have a standalone class without one
	public static void main(String [] args)
	{
		Scanner in = new Scanner(System.in);
		// read in the number of lines from the user
		System.out.print("Enter the number of lines: ");
		int numLines = in.nextInt();

		//method call to printStar method. Pass in numLines as a parameter.
		printStar(numLines);
	}

}