1#四则运算(用字典实现)2#Author: cnRick3#Time : 2020-4-34a =float(input())5op =input()6b =float(input())7try:8res = {'+':a+b,'-':a-b,'*':a*b,'/':a/b}9print("{:.2f}".format(res[op]))10except:11print("divided by zero")...