Python核心编程（第二版） 第六章习题答案

 1 #!/usr/bin/python
 2 
 3 import string
 4 import keyword
 5 import sys
 6 
 7 Startwith=string.letters+‘_‘
 8 Othersymbol=string.letters+‘_‘+string.digits
 9 def CheckID(s):
10         if s[0] in Startwith:
11                 if len(s)==1:
12                         print "The ID is valid"
13                         if s in keyword.kwlist:
14                                 print "And the ID is a key word"
15                 else:
16                         for j in s[1:]:
17                                 if j not in Othersymbol:
18                                         print "The other symbol is invalid."
19                                         sys.exit()
20                         print "The ID is valid."
21                         if s in keyword.kwlist:
22                                 print "And the ID is a key word"
23         else:
24                 print "The startwith is invalid."
25 
26 
27 
28 
29 if __name__=="__main__":
30         sid=raw_input("Enter a string:")
31         CheckID(sid)

 1 #!/usr/bin/python
 2 
 3 astring=raw_input("Enter a list of num:")
 4 alist=astring.split()
 5 print alist
 6 
 7 ilist=[]
 8 for s in alist:
 9         i=int(s)
10         ilist.append(i)
11 
12 print ilist
13 print sorted(ilist)
14 #print ilist.sort()
15 print sorted(alist)
16 #print alist.sort()

 1 !/usr/bin/python
 2 
 3 def value(num):
 4         if 90<=num<=100:
 5                 #print ‘A‘
 6                 return ‘A‘
 7         elif 80<=num<=89:
 8                 #print ‘B‘
 9                 return ‘B‘
10         elif 70<=num<=79:
11                 #print ‘C‘
12                 return ‘C‘
13         elif 60<=num<=69:
14                 #print ‘D‘
15                 return ‘D‘
16         elif num>=0 and num<60:
17                 #print ‘F‘
18                 return ‘F‘
19         else:
20                 print  "The num is invalid."
21 
22 
23 if __name__=="__main__":
24         vlist=[]
25         ilist=[56,34,78,90,62,81,100]
26         for i in ilist:
27                 vlist.append(value(i))
28         print vlist
29         print sorted(ilist)

 1 #!/usr/bin/python
 2 #encoding=utf-8
 3 #判断一个字符串是否重现(后面跟前面的一致).
 4 #附加题:在处理除了严格的回文之外,加入对例如控制符号和空格的支持。
 5 import sys
 6 
 7 def palindorom(s):
 8         l=len(s)
 9         if l%2<>0:
10                 print "The string is not palindorom."
11         else:
12                 for i in (0,int((l-1)/2)):
13                         if s[i]==s[-(i+1)]:
14                                 pass
15                         else:
16                                 print "The string is not palindorom."
17                                 sys.exit()
18                 print "The string is a palindorom."
19 
20 if __name__=="__main__":
21         astring=raw_input("Enter a string:")
22         palindorom(astring)

 1 #!/usr/bin/python
 2 #encoding:utf-8
 3 #接受一个字符,在其后面加一个反向的拷贝,构成一个回文字符串.
 4 
 5 original=raw_input("Enter a string:").strip()
 6 length=len(original)
 7 palindorom=original
 8 for i in range(1,length+1):
 9         palindorom=palindorom+original[-i]
10 
11 print palindorom

 1 #!/usr/bin/python
 2 #encoding:utf-8
 3 #创建一个 string.strip()的替代函数:接受一个字符串,去掉它前面和后面的
 4 #空格(如果使用 string.*strip()函数那本练习就没有意义了)
 5 
 6 original=raw_input("Enter a string:")
 7 length=len(original)
 8 print length
 9 for i in range(0,length):
10         if original[i]<>‘ ‘:
11                 lstrip=original[i:]
12                 print len(lstrip)
13                 break
14         else:
15                 pass
16 
17 
18 for i in range(1,length+1):
19         if lstrip[-1]<>‘ ‘:
20                 strip=lstrip
21                 break
22         elif lstrip[-i]<>‘ ‘:
23                 strip=lstrip[:-i+1]
24                 print len(strip)
25                 break
26         else:
27                 pass
28 
29 print strip

 1 #!/usr/bin/python
 2 
 3 num_str=raw_input("Enter a number:")
 4 
 5 num_num=int(num_str)
 6 
 7 fac_list=range(1,num_num+1)
 8 
 9 print "BEFORE:",fac_list
10 i=0
11 while i<len(fac_list):
12         if num_num % (fac_list[i])==0:
13                 del fac_list[i]
14         else:
15                 i=i+1
16 
17 print "AFTER:",fac_list