04 2023 档案
摘要：内容参照 相关阅读推荐 首先是递归获得阶乘的例子 (define f (lambda (x) (cond ((= x 1) 1) (else (* x (f (- x 1))))))) 对应的lambda (f): (lambda (f) (lambda (x) (cond ((= x 1) 1)
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摘要：(define (list-change total denoms) (define (cons-all num ls) (let ((num-val num)) (cond ((null? ls) nil) (else (cons (cons num (car ls)) (cons-all num
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摘要：def mutate_reverse(link): """Mutates the Link so that its elements are reversed. >>> link = Link(1) >>> mutate_reverse(link) >>> link Link(1) >>> link
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摘要：(define-macro (switch expr cases) (cons 'cond (map (lambda (case) (cons (eq? (eval expr) (car case)) (cdr case))) cases)) ) 这段代码是一个用于 Scheme 语言的宏定义，可以
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摘要：(define-macro (def func args body) `(define ,(cons func args) ,body)) 分析： 定义一个万能的函数定义，那就要模拟函数定义的样子。ok，函数定义是什么样子的呢？ eg: (define (filter-lst fn lst) (if
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摘要：#lang sicp (define (unique s) (if (null? s) nil (cons (car s) (unique (filter (lambfa (x) (not (eq? x (car s)))) (cdr s))) ) ) ) 这是一个Scheme函数，名为unique
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摘要：1.list quote quasiquote The list procedure takes in an arbitrary amount of arguments. Because it is a procedure, all operands are evaluated when list
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摘要：Write sub-all, which takes a list s, a list of old words, and a list of new words; the last two lists must be the same length. It returns a list with
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摘要：item 1: 使用断言 item 2: Just end all of your lines with a comma
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摘要：def reduce_armor(self, amount): """Reduce armor by AMOUNT, and remove the FireAnt from its place if it has no armor remaining. Make sure to damage eac
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摘要：题目： def is_bst(t): """Returns True if the Tree t has the structure of a valid BST. >>> t1 = Tree(6, [Tree(2, [Tree(1), Tree(4)]), Tree(7, [Tree(7), Tr
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摘要：重点：： 观察到：在带入函数之后，没有任何返回值，是直接对参数本身进行作用。遇到这种情况就必须在基线条件下多加一个 【return】语句 why? 其实就是人为两种情况，第一种就是t是节点，此时只需要将节点平方就可以了。第二种情况就是有分支，首先呢就将root平方，再将分支进行处理。 1 def l
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摘要：#include<iostream> using namespace std; int f(int** r, int ** s){ int temp= **r; int temp2=**s; int * z=*r; *r=*s; *s=z; printf("**r= %d\n",**r); prin
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摘要：题目：about generator Write the generator function make_generators_generator, which takes a zero-argument generator function g and returns a generator th
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摘要：def close(n, smallest=10, d=10): """ A sequence is near increasing if each element but the last two is smaller than all elements following its subsequ
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摘要：pre_old_time: /*** 然后按下enter按键，就可以用n来跳转 N回跳 编辑模式下 输入 【 ：noh 】 可以取消高亮 从当前行开始进入编辑模式 vim f命令可以定位到指定字符，；右重复，,向左重复 移动到前一个单词的末尾：ge d0：删除当前位置到行开头的所有内容，不会删除光标
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摘要：Problem 2 题目描述： 代码： 1 def inc_subseqs(s): 2 """Assuming that S is a list, return a nested list of all subsequences 3 of S (a list of lists) for which
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