I thought I was the only one.

Imagine you do the following (that may not be the thing you must do actually to solve the kata cause it could be too inefficient, but to help you understand):

• For each number in the array, find its decomposition in prime factors.
• Gather all the prime factors you've found in the previous step in a single sorted array without duplicate.
• For each prime factor P in the array of the previous step, make a pair which first element is P itself, and which second element is the sum of the elements of the input array that include P in their prime factor decomposition. That's your output.

I didn't do much more than rewording the description. If it's still not clear it may be that it's hard to explain it more easily...

me too

me too

me too

The problem is in this line, passing by reference:

list(&$i, &$even, &$odd, &$t) = $acc;

That's where the compiler throws that error, maybe those playgrounds use a different PHP version? In this kata the only version available is 7.0 right now

Not a kata issue, read this please: https://docs.codewars.com/training/troubleshooting/ and post your code as instructed there if you need help with it.

PHP Completions 908

That error is caused by your code.

That error comes from your code, not a kata issue, please, read this: https://docs.codewars.com/training/troubleshooting/