/*
Total squares in a 3 * 3 grid are 14
1x1 squares = 9 Squares
2x2 squares = 4 Squares
3x3 squares = 1 Squares
*/
function countSquaresInNxNGrid($N) {
// Formula: Total Squares = N * (N + 1) * (2N + 1) / 6
return ($N * ($N + 1) * (2 * $N + 1)) / 6;
}
$N = 3;
// Validate input
if ($N <= 0) {
echo "Grid size must be a positive integer!\n";
exit(1);
}
$totalSquares = countSquaresInNxNGrid($N);
echo "The total number of squares in a {$N}x{$N} grid is: {$totalSquares}\n";
/*
run:
The total number of squares in a 3x3 grid is: 14
*/