#include <stdio.h>

main()
{

int n, r, s, a; //side length, row number, space, asterisk

printf ("Diamond side length: ");
scanf ("%d", &n);

if (n > 0)
	{
	for (r = 1; r <= n; ++r) // for lines
		{
		for (s = 1; s <= n - r; ++s) // for spaces
		printf(" ");
			{
			for (a = 1; a <= (2 * r) - 1; ++a) // for asterisks    
			printf ("*");
			printf ("\n");
			}
		}

	for (r = n - 1; r > 0 ; --r)
		{
		for (s = 1; s <= n - r; ++s)
		printf (" ");
			{
			for (a = 1; a <= (2 * r) - 1; ++a)
			printf ("*");
			printf ("\n");
			}
		}
	return 0;
	}
 else
	{
	printf ("Yeah right! I can't make a diamond with that side length.\n");
	return 1;
	}
}