Question

This problem was asked by Jane Street. cons(a, b) constructs a pair, and car(pair) and cdr(pair) returns the first and last element of that pair. For example, car(cons(3, 4)) returns 3, and cdr(cons(3, 4)) returns 4. Given this implementation of cons: def cons(a, b): def pair(f): return f(a, b) return pair Implement car and cdr.

                    
							

def cons(a, b):
    def pair(f):
        return f(a, b)
    return pair

def car(f):
    def first(a, b):
        return a
    return f(first)

def cdr(f):
    def second(a, b):
        return b
    return f(second)

print("1st element of pair: {}\n2nd element of pair: {}".format(car(cons(1,5)),cdr(cons(1,5))))