#方法1

def add(x,y):

    return x+y

def dec(x,y):

    return x-y

def multi(x,y):

    return x*y

def div(x,y):

    return x/y

operater = {'+':add,'-':dec,'*':multi,'/':div}

def calculator(x,o,y):

    return operater.get(o)(x,y)

#方法2

def calculator1(x,o,y):

    return {'+':x+y,'-':x-y,'*':x*y,'/':x/y}.get(o)

def test():

    print calculator(2, '*', 6)

    print calculator1(2,'+',6)

if __name__ == "__main__":

    test()