[lisp] scheme环境搭建与编译运行
搭建环境参考这篇
http://leochin.com/mac-scheme-install/
用文本编辑器写代码 保存文件格式为 .scm
在终端中cd到scm文件所在文件夹,
执行 (cf "scm_name")编译文件
然后执行 (load "scm_name.scm")加载文件,加载过程中会把文件执行一遍,就像Python一样,或者应该反过来说。
下面是几个lisp程序,参考书籍 SICP
求余:
1 (define (remainder m n)( 2 if (< (- m n) n) 3 (- m n) 4 (remainder (- m n) n) 5 ) 6 )
牛顿法求开方:
1 (define (sqrt x) 2 (define (sqrt_iter guess x) 3 (if (good_enough? guess x) 4 guess 5 (sqrt_iter (improve_guess guess x) 6 x ))) 7 8 9 (define (improve_guess guess x) 10 (average guess (/ x guess))) 11 12 (define (average a b) 13 (/ (+ a b) 2)) 14 15 (define (good_enough? guess x) 16 (< (abs (- (square guess) x)) 0.001)) 17 18 (define (square x) (* x x)) 19 20 (define (abs x) 21 (if (< x 0) 22 (- x) 23 x) 24 ) 25 (sqrt_iter 1.0 x) 26 )
阶乘:
1 (define (factorial n) 2 (fact_iter 1 1 n)) 3 4 (define (fact_iter res count n) 5 (if (> count n) 6 res 7 (fact_iter (* res count) (+ count 1) n)))
求幂:
1 (define (expt x n)( 2 expt_iter x 1 n) 3 ) 4 5 (define (expt_iter x res n)( 6 if (= n 0) 7 res 8 (expt_iter x (* x res) (- n 1)) 9 ) 10 )
最大公约数:
(define (gcd m n)( if (= n 0) m (gcd n (remainder m n)) ))
fibonacci:
1 (define (fib n) 2 (fib_iter 1 0 n) ) 3 4 (define (fib_iter next pre count)( 5 if (= count 0) 6 pre 7 (fib_iter (+ pre next) next (- count 1)) 8 ))
1 (define (fib n) 2 (if (< n 2) 3 1 4 (+ (fib (- n 1)) 5 (fib (- n 2)))))