我对php中的以下代码感到困惑

Question

The code is as follow-

<?php
$i = 5;
while (--$i > 0 || ++$i)
{   
    print $i;
}
?>

The correct answer is 4321111........ But how could it start from 4, it should just strat from 5. In my opinion, the answer should be 55555555.......

Answer 1

it starts with 4 because this statement is evaluated first (--$i > 0 )

which is pre decrement, that means it decrements first then evaluates the while loop

so here it is checking whether i is greater than 0 or else increment i by 1

so it prints 4321, when i reaches 0 the --$i > 0 statement is not evaluated as i becomes 0 so the or part is evaluated which is +1

so the result becomes 4321111111.................