# 異常的捕獲
a=int(input('輸入除數:'))
b=int(input('輸入被除數:'))
try:
    res=a/b
except ZeroDivisionError:
    print('除數不可以為0')
    # 相同處理方式的異常可以這么寫
except (BaseException,TypeError):
    print('有錯誤')
else:
    print('您的結果為',res)
finally:
    print('感謝使用!')

'''
3 錄入一個學生的成績，把該學生的成績轉換為A優秀、B良好、C合格、D不及格的形式，
最后將該學生的成績打印出來。要求使用assert斷言處理分數不合理(小于0或者大于100)的情況
請編寫程序。
'''

n=int(input())
assert n in range(101),"您輸入的成績不合理！"
if n>=85:
	print("優秀！")
elif n>=70:
	print("良好！")
elif n>=60:
	print("合格！")
else:
	print("不及格！")

'''
自己定義一個異常類，繼承Exception類, 捕獲下面的過程：判斷input()輸入的字符串長度是否小于5， 
如果小于5，比如輸入長度為3則輸出:"The input is of length 3, expecting at least 5“，
大于5則輸出"success”。 
'''
class StrLenError(Exception):
	def __init__(self,s):
		Exception.__init__(self,s)
		self.s =s
	def __str__(self):
			return f"The input is of length {len(self.s)}, expecting at least 5"
n=input()
if len(n)<=5:
	raise StrLenError(n)
else:
	print("success")

>>> class NewError(Exception):
        def __init__(self, value):
            self.value = value
        def __str__(self):
            return repr(self.value)
   
>>> try:
        raise NewError(2*2)
    except NewError as e:
        print('New exception occurred, value:', e.value)
   
My exception occurred, value: 4
>>> raise NewError('oops!')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
__main__.NewError: 'oops!'

class Error(Exception):
    """Base class for exceptions in this module."""
    pass

class InputError(Error):
    """Exception raised for errors in the input.

    Attributes:
        expression -- input expression in which the error occurred
        message -- explanation of the error
    """

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

class TransitionError(Error):
    """Raised when an operation attempts a state transition that's not
    allowed.

    Attributes:
        previous -- state at beginning of transition
        next -- attempted new state
        message -- explanation of why the specific transition is not allowed
    """

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