一个关联数组上的PHP多数组值

$students = array(
    "Alice" => array("Math" => 90, "Science" => 85),
    "Bob" => array("Math" => 88, "Science" => 92),
    "Charlie" => array("Math" => 78, "Science" => 88)
);

echo $students["Alice"]["Math"]; // 输出: 90
echo $students["Bob"]["Science"]; // 输出: 92

$students["David"] = array("Math" => 95, "Science" => 90);

foreach ($students as $name => $subjects) {
    echo "$name's scores:<br>";
    foreach ($subjects as $subject => $score) {
        echo "$subject: $score<br>";
    }
    echo "<br>";
}

$students["Eve"] = array("Math" => 89, "Science" => 91);

$students["Alice"]["Math"] = 92;

unset($students["Charlie"]);