Thread: What's Wrong With This?

Code:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int main()
{
	char cBoard[3][3] = {0};
	int x;
	int y;
	int z = 0;
	int iSquare;
	printf("Enter a square number <1-9>: ");
	scanf("%d", &iSquare);
	for (x=1; x <= 3; x++)
	{
		for (y=1; y <= 3; y++)
		{ 
			z++;
			if (iSquare == z)
			{
				if (cBoard[x-1][y-1] == NULL)
				{
					printf("\n\n%d is Empty!\n\n", iSquare);
				}
				else
				{	
					printf("looped %d times", z);
					printf("\n\n%d IS FULL!\n\n", iSquare);
				}
			}
		}
	}
return 0;
}

[mag1x@localhost ~]$ gcc wtf.c -o wtf
wtf.c: In function ‘main’:
wtf.c:21: warning: comparison between pointer and integer

I don't understand. Does that mean my program is wrong? Thanks.