pub type Gcf<A, B> = <A as Gcd<B>>::Output;
Alias for the associated type of Gcd: Gcf<A, B> = <A as Gcd<B>>::Output>
Gcd
Gcf<A, B> = <A as Gcd<B>>::Output>
Note: Encountered an error during type layout; the type failed to be normalized.