Python核心编程2第六章课后练习

6-1 字符串 .string 模块中是否有一种字符串方法或者函数可以帮我鉴定一下一个字符串是否是另一个大字符串的一部分? 

#!/usr/bin/env python
def contain(str1,str2):
        if str1 in str2:
                print "str1 contains str2"
        else:
                print "str1 not contains str2"
if __name__=="__main__":
        str1=raw_input("please type the string1:")
        str2=raw_input("please type the string2:")
        contain(str1,str2)

6-2 字符串标识符.修改例 6-1 的 idcheck.py 脚本,使之可以检测长度为一的标识符,并且可以识别 Python 关键字,对后一个要求,你可以使用 keyword 模块(特别是 keyword.kelist)来帮你.

#!/usr/bin/env python
import string
import keyword
alphas=string.letters+'_'
nums=string.digits
keywords=keyword.kwlist
print 'Welcome to the Identifier Checker v1.0'
print 'Testees must be at least 2 chars long.'
myInput=raw_input('Identifier to test?')
if myInput in keywords:
                print "%s can not be the keyword"%myInput
elif len(myInput)>1:
        if myInput in keywords:
                print "chars can not contain the keywords"
        if myInput[0] not in alphas:
                print '''invalid:first symbol must be alphabetic'''
        else:
                for otherChar in myInput[1:]:
                        if otherChar not in alphas +nums:
                                print '''invalid:remaining symbols must be alphanumeric'''
                                break
                else:
                        print "okay as an identifier"
else:
        print "The word is illegal identifier for python"

6-3  排序 

 (a) 输入一串数字,从大到小排列之. 

#!/usr/bin/env python
#-*-coding:utf-8-*-
string=raw_input("please enter the string:")
print sorted(string)

  (b) 跟 a 一样,不过要用字典序从大到小排列之.

#!/usr/bin/env python
string =raw_input("please enter the number:")
list =string.split()
print list
print sorted(list)