4.4作业

10-4 访客名单

file_name = "test.out.txt"

with open(file_name, 'w') as file:

while True:

user_name = input("Please enter your name(enter \'q\' to quit): ")

if user_name == 'q':

break

file.write(user_name + '\n')

10-6 加法运算

while True:

try:

lhs = int(input("first number: "))

rhs = int(input("second number: "))

except ValueError:

print("Not a number!")

else:

print(lhs + rhs)

10-12 记住喜欢的数字

import json

def load_favorite_number():

file_name = 'test.json'

try:

with open(file_name, 'r') as file:

favorite_number = json.load(file)

except FileNotFoundError:

return None

else:

return favorite_number

def input_favorite_number():

while True:

try:

favorite_number = int(input("Please enter your favorite number: "))

except ValueError:

print("Not a number!")

else:

return favorite_number

def save_favorite_number(favorite_number):

file_name = 'test.json'

with open(file_name, 'w') as file:

json.dump(favorite_number, file)

favorite_number = load_favorite_number()

if not favorite_number:

favorite_number = input_favorite_number()

save_favorite_number(favorite_number)

print("Your favorite number is: " + str(favorite_number))