hitung ipk, PHP

ipk.php

<?php

function A2N($alphabet) {
	$alphabet = strtoupper($alphabet);
	$result = -(ord($alphabet) - 69);
	
	return $result > 0 && $result <= 4 ? $result : 0;
}

function calculateGPA($grades) {
	$tmp = [0, 0];
	foreach ($grades as $grade) {
		$tmp[0] += A2N($grade[1]) * $grade[0];
		$tmp[1] += $grade[0];
	}
	
	return number_format($tmp[0] / $tmp[1], 2);
}


$grades = [
// ['credits', 'alphabet']
// semester 1
	[3, 'A'],
	[3, 'B'],
	[3, 'C'],
	[3, 'B'],
	
// semester 2
	[3, 'B'],
	[3, 'A'],
	[3, 'B'],
	[3, 'A'],
	
// semester 3
	[3, 'B'],
	[3, 'B'],
	[3, 'B'],
	[3, 'A'],
];



header('Content-Type: text/plain');
foreach ($grades as $grade) {
	echo "sks: {$grade[0]}\tgrade: {$grade[1]}" . PHP_EOL;
}

echo PHP_EOL;
echo 'GPA => ' . calculateGPA($grades);
exit;