how do i loop through an associative array with multiple values

Question

I just started learning php and I have this issue. I'm trying to loop through this array to get the total value of each key and output the student with the highest number. I'd really appreciate your inputs

$students = array(
        'Mary' => [20,45,12],
        'Grace' => [40,78,56],
        'John' => [61,37,58]
);

The expected output should be Grace but i can't seem to get it to work.

Answer 1

You don't have to loop. Just calculate all the totals

$totals = array_map('array_sum', $students);

then output the key of the array with the maximum total.

echo array_keys($totals, max($totals))[0];

Answer 2

Something like this maybe assuming all grades will be positive

$students = array(
    'Mary' => [20,45,12],
    'Grace' => [40,78,56],
    'John' => [61,37,58]
);

$highest_grade = 0;
$higest_person = "";

foreach($students as $key => $value) {
    $max = max($value);
    if ($highest_grade <= $max) {
        $highest_grade = $max;
        $highest_person = $key;
    }
}
echo $highest_person . '->' . $highest_grade;

Output is using http://phptester.net/

Grace->78