Python基础练习100题 ( 51~ 60）

摘要：刷题继续昨天和大家分享了题，今天继续来刷题解法一解法一解法一解法二解法一解法二解法一解法二解法三解法一解法一解法一解法一解法一源代码下载这十道题的代码在我的上，如果大家想看一下每道题的输出结果，可以点击以下链接下载

昨天和大家分享了41-50题，今天继续来刷51~60题

Write a function to compute 5/0 and use try/except to catch the exceptions.

def divide():
    return 5/0

try:
    divide()
except ZeroDivisionError as ze:
    print("Why you are dividing a number by ZERO!!")
except:
    print("Any other exception")

Define a custom exception class which takes a string message as attribute.

class CustomException(Exception):
    """Exception raised for custom purpose
    Attributes:message -- explanation of the error
    """

    def __init__(self, message):
        self.message = message

num = int(input())
try:
    if num < 10:
        raise CustomException("Input is less than 10")
    elif num > 10:
        raise CustomException("Input is grater than 10")
except CustomException as ce:
    print("The error raised: " + ce.message)

Assuming that we have some email addresses in the "username@companyname.com" format, please write program to print the user name of a given email address. Both user names and company names are composed of letters only.
Example:
If the following email address is given as input to the 
program:

john@google.com

Then, the output of the program should be:

john

In case of input data being supplied to the question, it should be assumed to be a console input.

def getname(s):
    try:
        return s.split("@")[0]
    except:
        print("This is not a email-adress")

getname("john@google.com")

import re

email = "john@google.com"
pattern = "(w+)@w+.com"
ans = re.findall(pattern,email)
print(ans)

Assuming that we have some email addresses in the "username@companyname.com" format, please write program to print the company name of a given email address. Both user names and company names are composed of letters only.
Example:
If the following email address is given as input to the program:

john@google.com

Then, the output of the program should be:

google

import re

email = "john@google.com"
pattern = "w+@(w+).com"
ans = re.findall(pattern,email)
print(ans)

def getname(s):
    try:
        return s.replace("@",".").split(".")[1]
    except:
        print("Something Wrong")

getname("john@google.com")

Write a program which accepts a sequence of words separated by whitespace as input to print the words composed of digits only.
Example:
If the following words is given as input to the program:

2 cats and 3 dogs.

Then, the output of the program should be:

["2", "3"]

In case of input data being supplied to the question, it should be assumed to be a console input.

import re
s = input()
print(re.findall("d+",s))

import re
s= input()
pattern = "d+"
ans = re.findall(pattern,s)
print(ans)

[int(s) for s in input().split() if s.isdigit()]

Print a unicode string "hello world".

unicodeString = u"hello world!"
print(unicodeString)

Write a program to read an ASCII string and to convert it to a unicode string encoded by utf-8.

s = input()
u = s.encode("utf-8")
print(u)

Write a special comment to indicate a Python source code file is in unicode.

# -*- coding: utf-8 -*-

Write a program to compute 1/2+2/3+3/4+...+n/n+1 with a given n input by console (n>0).
*Example:
If the following n is given as input to the program:*

5

Then, the output of the program should be:

3.55

n = int(input())
sum = 0
for i in range(1, n+1):
    sum+= i/(i+1)
print(round(sum, 2))  # rounded to 2 decimal point

Write a program to compute:

f(n)=f(n-1)+100 when n>0
and f(0)=1

with a given n input by console (n>0).
Example:
If the following n is given as input to the program:

5

Then, the output of the program should be:

501

def f(n):
    if n == 0:
        return 1
    else:
        return f(n-1) + 100

n = int(input())
print(f(n))

这十道题的代码在我的github上，如果大家想看一下每道题的输出结果，可以点击以下链接下载：

Python 51-60题

我的运行环境Python 3.6+,如果你用的是Python 2.7版本，绝大多数不同就体现在以下3点：

raw_input()在Python3中是input()

print需要加括号

fstring可以换成.format(),或者%s，%d

谢谢大家，我们下期见！希望各位朋友不要吝啬，把每道题的更高效的解法写在评论里，我们一起进步！！！