将PHP_INT_MAX与数组一起使用会对性能产生影响吗？

Question

For example I have the following code

$array = [];
$array[0] = 0;
$array[1] = 1;
$array[2] = 'max';

foreach ($array as $value) {
    // code
}

I want to know is there any performance impact when I use PHP_INT_MAX as the index of a array like so.

$array = [];
$array[0] = 0;
$array[1] = 1;
$array[PHP_INT_MAX] = 'max';

foreach ($array as $value) {
    // code
}

Regardless whether yes or not, anybody can tell me the reason? Thanks!

Answer 1

No, the array still only has 3 elements, so only 3 elements exist in memory.

It doesn't really matter what the keys are for those elements, though there's a slight memory overhead for long string keys because PHP maintains the key as well as the value and longer strings use more memory than shorter strings; but in this case, your keys are integers which are fixed size, whether the value is -1, 0, 98 or PHP_INT_MAX