earn the python in hard way习题26~30的附加习题

书本：“笨办法”学Python

版本：第3版

作者：Zed A.Shaw

这些答案都是我自己思考的，不能保证百分百对。我只是想让其他人学习这本书在做附加题练习的时候能有一个参考。如果哪里有错了，欢迎大家讨论~

习题26 附加题练习

修改后的代码

# -*- coding:utf -8 -*-
def break_words(stuff):
"""This function will break up words for us."""
words = stuff.split(' ')
return words

def sort_words(words):
"""Sorts the words."""
return sorted(words)

def print_first_word(words):                                        #冒号没有
"""Prints the first word after popping it off."""
word = words.pop(0)                                             #pop多打了一个o
print word

def print_last_word(words):
"""Prints the last word after popping it off."""
word = words.pop(-1)                                            #‘ ）’没有
print word                                                      #不知道哪里错了，重新打一遍

def sort_sentence(sentence):
"""Takes in a full sentence and returns the sorted words."""
words = break_words(sentence)
return sort_words(words)

def print_first_and_last(sentence):
"""Prints the first and last words of the sentence."""
words = break_words(sentence)
print_first_word(words)
print_last_word(words)

def print_first_and_last_sorted(sentence):
"""Sorts the words then prints the first and last one."""
words = sort_sentence(sentence)
print_first_word(words)
print_last_word(words)

import ex25                                                     #会用到ex25.py的参数
print "Let's practice everything."
print 'You\'d need to know \'bout escapes with \\ that do \n newlines and \t tabs.'

poem = """
\tThe lovely world
with logic so firmly planted
cannot discern \n the needs of love
nor comprehend passion from intuition
and requires an explantion
\n\t\twhere there is none.
"""

print "--------------"
print poem
print "--------------"

five = 10 - 2 + 3 - 5
print "This should be five: %s" % five

def secret_formula(started):
jelly_beans = started * 500
jars = jelly_beans / 1000                                   #除法的符号错了
crates = jars / 100
return jelly_beans, jars, crates

start_point = 10000
beans, jars, crates = secret_formula(start_point)               #等号多打一个,参数下划线打错了

print "With a starting point of: %d" % start_point
print "We'd have %d jeans, %d jars, and %d crates." % (beans, jars, crates)

start_point = start_point / 10

print "We can also do that this way:"
print "We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_point)   #‘）’没有，参数打错了

sentence = "All god \t things come to those who weight."        #\t 要用空格隔开

words = ex25.break_words(sentence)
sorted_words = ex25.sort_words(words)

print_first_word(words)
print_last_word(words)
print_first_word(sorted_words)                                  #语句前面多了 ‘ . ’
print_last_word(sorted_words)
sorted_words = ex25.sort_sentence(sentence)
print sorted_words                                              #print 符号打错了

print_first_and_last(sentence)                                  #函数名打错了

print_first_and_last_sorted(sentence)                           #sentence打错了,缩进去掉,函数名打错了

习题28 附加题练习

>, >=, <, <=, <>, !=, ==。

表格内容

等价运算操作符	‘>’	‘>=’	‘<’	‘<=’	‘<>’	‘!=’	‘==’
名称	大于	大于等于	小于	小于等于	不等于	不等于	等于

3. 在终端中打开python，输入布尔操作查看输出的布尔值。

4. 写在笔记本上了，不想撕掉。

习题29 附加题练习

判断下一行代码是否执行。true执行，false不执行。

告诉python缩进的代码块是属于这个if语句的。

会报错

可以。

输出可能会变得不同。

习题30 附加题练习

elif的功能与if一样的；else是在前面if和elif都不执行的情况下，执行else下的代码块。

把三个参数改了，输出可能会不同。

不写

注释