一个简单例子阐明while True与if的配合使用方法

#!/usr/bin/env python
oldboy_age = 56

#while True 是个死循环，需要用break来退出

while True:
    get_num = int(input("Pls guess oldboy\'s age:"))
    if get_num == oldboy_age:
        print("Oldboy is {age} years old.".format(age=get_num))
        break
    elif get_num > oldboy_age:
        print("Your input is larger than his age.")
    else:
        print("Your input is smaller than his age.")

运行结果：

D:\Python\Python36\python.exe "E:/python 14/day0101.py"
Pls guess oldboy's age:99
Your input is larger than his age.
Pls guess oldboy's age:22
Your input is smaller than his age.
Pls guess oldboy's age:56
Oldboy is 56 years old.

Process finished with exit code 0