#include <stdio.h>

void Print(char c, int n);	// print c, n times
void Print(char c, int n)
{
	int i;
	for (i=0; i < n; i++)
		printf("%c", c);
}

// draw a diamond of a given diameter (odd positive integer n)
void DrawDiamond(int n);
void DrawDiamond(int n)
{
	int line, space, star;

	// check parameter n to be positive integer and odd!
	if (n < 1 || (n%2==0)) return;

	// draw diamond: divide and conquer
	// step1: draw top triangle

	space = n/2; 	// go all the way to 0, space--
	star = 1;	// go all the way to n, star+=2

	for(line = 0; line < (n+1)/2; line++)
	{
		Print(' ', space);
		Print('*', star);
		space--;
		star+=2;
		Print('\n', 1);
	}


	// step2: draw bottom upside down triangle
	
	space = 1;	// space++
	star = n-2;	// star-=2
	for(line = 0; line < n/2; line++)
	{
		Print(' ', space);
		Print('*', star);
		space++;
		star-=2;
		Print('\n', 1);
	}
}




int main()
{

	DrawDiamond(5);
	DrawDiamond(7);
	DrawDiamond(9);
	DrawDiamond(11);

	return 0;
}