PHP基本操作符

Question

Just came across this problem, would you mind explaining how this end up having an answer of 4? So basic yet I have no idea how it happened.

echo $a = 20%-8; //4

Answer:

echo (5 % 3)."
";           // prints 2
echo (5 % -3)."
";          // prints 2
echo (-5 % 3)."
";          // prints -2
echo (-5 % -3)."
";         // prints -2

Answer 1

You're trying to get a modulo of negative number. There's no difference between this and: 20%8

See: https://math.stackexchange.com/questions/519845/modulo-of-a-negative-number