C-Invariance: +1/-1 for Decay Forbidden/Allowed

[Howlin]

Homework Statement

Which of the folowing decays are forbidden by C-iinvariance
ω° = π° + γ
η' = ρ° + γ
π° = γ +γ + γ

Homework Equations

None

The Attempt at a Solution

The answers are meant to be:
ω° = π° + γ
-1 : (+1) (-1) -> Allowed
η' = ρ° + γ
+1 -> (-1) (-1) -> Allowed

π° = γ +γ + γ
+1 -> (-1)(-1)(-1) -> forbidden

My question is where are those +1 and -1 gotten from, I have tried to find what values to put for the particles but cannot fund them anywhere.
Does anyone know if the three are right and if so where I can get the +1 or -1?

 

[mfb]

You can find the C quantum number at the http://pdglive.lbl.gov/listings1.brl?quickin=Y , for example. Even Wikipedia should have them...