max - How do I use a pair to find which of two functions will evaluate the largest value? Scheme -


basically there pair made of 2 functions , code has take pair input x find highest evaluation x , print evaluation.
receive error : car: contract violation expected: pair? given: 4

define (max x)    (lambda (x)     ;i wanted lambda highest suitable function  (if (> (car x) (cdr x))         (car x)         (cdr x))))   (define one-function (lambda (x) (+ x 1)))  (define second-function (lambda (x) (+ (* 2 x) 1)))  ;my 2 functions  ((max (cons one-function second-function)) 4)

and functions being called? , have two parameters called x, must have different names. try this:

(define (max f)                     ; must use different parameter name   (lambda (x)     (if (> ((car f) x) ((cdr f) x)) ; call functions         ((car f) x)         ((cdr f) x))))

now it'll work expected:

((max (cons one-function second-function)) 4) => 9

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