題目要求:
用多分支結構編寫一個程序實現四則運算器(+,-,*,/)。
當輸出合法的時候,輸出表達式及運算結果;
輸入不合法時,輸出Error。
輸入輸出示例:
代碼如下:
class calculator:#定義計算器類,包含加減乘除和小數位
def __init__(self,a,b):
self.a =a
self.b = b
def addition(self,retain):
return round(self.a+self.b, retain)
def division(self,retain):
return round(self.a/self.b, retain)
def subtraction(self,retain):
return round(self.a-self.b, retain)
def multiplication(self, retain):
return round(self.a*self.b, retain)
while 1:#一直循環計算下去
getNum1 = input('請輸入第一個數:')
try:
float(getNum1)#判斷是否爲數字
except ValueError:
print("Error")#不是數字則輸出Error,程序終止
break
opera = input('請輸入符號:')#輸入加減乘除運算符號
getNum2 = input("請輸入第二個數:")
try:
float(getNum2)
except ValueError:
print("Error")
break
getRetain = input('請輸入保留小數位數:')
result = 0.00
num1 = float(getNum1)
num2 = float(getNum2)
Retain = int(getRetain)#計算小數位
if opera =='+':
result = calculator(num1,num2).addition(Retain)
elif opera =='-':
result = calculator(num1,num2).subtraction(Retain)
elif opera =='*':
result = calculator(num1,num2).multiplication(Retain)
else:
result = calculator(num1,num2).division(Retain)
print(result)
運行結果: