<?php
//input
$input = trim(fgets(STDIN));
$token = '*';
//calculations
for ($x = 1; $x <= $input; $x++){
	for($y = 1; $y <= $input; $y++){
		if ($token == '*'){
		echo $token;
		$token = 'X';
		}
		else{
		echo $token;
		$token = '*';
}
}
echo '!';
echo PHP_EOL;
}





?>