function evaluation

A function f defined on stacks of integers satisfies the following properties. f(∅) = 0 and f (push (S, i)) = max (f(S), 0) + i for all stacks S and integers i. If a stack S contai...

$$f\left( {A,B} \right) = A' + B$$ Simplified expression for function $$f((x+y,y),z)$$ is

What value would the following function return for the input x = 95? Function fun (x:integer):integer; Begin If x > 100 then fun : x – 10 Else fun : fun(fun (x + 11)) End;