Cpttrn1

#include
using namespace std;

int main() {

int t;
int l;
int c;
cin >> t;
while(t--!=0)
{
	cin >> l;
	cin >> c;
for (int i = 0; i<l; i++)
{
	for(int j = 0; j<c; j++)
	{
		if((i+j)%2==0)
		{
			cout << "*";
		}else
		{
			cout<< ".";
		}
		cout << "\n";
	}
}
}
return 0;

}

Can some one help me out it’s giving me wrong answer.