

num1= float(raw_input("Enter a first number: "))
op= raw_input("enter an operator: ")
num2= float(raw_input("Enter a second number: "))

if op=="+":
    print (num1+num2)
elif op== "*":
    print (num2*num1)
elif op=="/":
    print (num1/num2)
else:
    print ("invalid operation")

