Hollow Diamond Pattern

How do I make this work for even number of rows?

#include
using namespace std;

int main() {

int n,k,c;
cin >> n;

	c = ((n+1)/2)-1;
	k = ((n+1)/2)+1;

for(int i = 1; i <= n; i++)
{
	if(i <= (n+1)/2)
	{
		--k;
		++c;	
	}
	else
	{
		++k;
		--c;
	}
	
	for(int j = 1; j <= n; j++)
	{
		if(j <= k || j >= c)
			cout << "*";
		else
			cout << " ";
	}
	cout << endl;
}
return 0;

}