Past exam question:
What my understanding of B-reduction is : Find all occurrences of the parameter in the output, and replace them with the input and that is what it reduces to
(λ param . output)input => output [param := input] => result
(λx.xy)z = (xy)[x:=z] = (zy) = zy
But I do not know how to use B-reduction on the expression above. What is the input, output and the parameter.