These are my code,

;;(calc-depth L) ;;The calc-depth function takes a list L and returns its depth. ;;The depth of a list is defined as the maximum level of "nesting" of a list. ;;A list with no sublists has a depth of 1; a list with sublists that don't have sublists has a depth of 2; a list with sublists that have sublists that don't have sublists has a depth of 3; and so on. (define calc-depth (lambda (L) (cond ((empty? L) 1) ((list? (first L)) (+ (calc-depth (first L)) (calc-depth (rest L)))) (else (calc-depth (rest L)))))) (check-expect (calc-depth '()) 1) (check-expect (calc-depth '(1 (2) 3)) 2) (check-expect (calc-depth '(1 (2 (3) 4) 5)) 3) (check-expect (calc-depth '(1 (2) 3 (4 (5)))) 3) ;;problem.