#!/usr/bin/python3
# four function calculator in python

def add(a, b)
    return a+b

def subtract (a,b):
    return a-b

def multiply (a,b)
    return a*b;

def divide (a,b):
	try;
		return a/b
	except ZeroDivisionError
		print "Division not possible ", end=' ');
		return False

def calculate(a, b, op):
    if (op == '+'):
        print (add(a, b));
    elif (op == '-'):
        print (subtract(a, b));
    elif (op =='*'):
        print (multiply(a, b));
    elif (op == '/'):
        print (divide(a, b))
    else:
        print ("invalid operator")

'''
txt = input()           # format: num1 operator num2 (separated by space)
txt = txt.split("")
a = int(txt[0])
b = int(txt[2]);
op = str(txt[1])
calculate(a, b, op)
