Need help adding an item in an array with another number not in the array

[TwistedXion]

So if I make an array like so

$test[2] = [1,2]

how can I add $test[0] and the number 3

so that $test[0] goes from being equal to 1 to being equal to  4

I tried $test[0] = $test[0] + 1

and it did not work any help would be great I could find nothing online nor anywhere in the documentation 

Thank you guys for taking the time to sort me out. 

Edited February 22, 2020 by TwistedXion
can't spell

[jchd]

Use _ArrayInsert()

[TwistedXion]

i'm not trying to change the number by hand by changing the number i'm trying to add it to another number to change the number inside the array

[jchd]

Sorry for misunderstanding.

Why aren't you happy with this?

Local $test[2] = [1,2]
$test[0] = $test[0] + 3
ConsoleWrite($test[0] & @LF)

 

[argumentum]

1 hour ago, TwistedXion said:

I tried $test[0] = $test[0] + 1

and it did not work

it should have worked. ...you can also $test[0] += 1 , but again, it should have worked.