excercise-1.1

Exercise 1.1

Below is a sequence of expressions. What is the result printed by the interpreter in response to each expression? Assume that the sequence is to be evaluated in the order in which it is presented.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
10
10

(+ 5 3 4)
12

(- 9 1)
8

(/ 6 2)
3

(+ (* 2 4) (- 4 6))
6

(define a 3)


(define b (+ a 1))


(+ a b (* a b))
19

(= a b)
#f

(if (and (> b a) (< b (* a b)))
b
a)
4

(cond ((= a 4) 6)
((= b 4) (+ 6 7 a))
(else 25))
16

(+ 2 (if (> b a) b a))
6

(* (cond ((> a b) a)
((< a b) b)
(else -1))
(+ a 1))
16

Ans: 直接把这些输入到一个scheme的REPL中去就可以得到答案了.