# -*- coding: utf-8 -*-

import math

#the function to calculate entropy, you should use the probabilities as the parameters

def entropy(*c):

    result=-1;

    if(len(c)>0):

        result=0;

    for x in c:

        result+=(-x)*math.log(x,2)

    return result;

if (__name__=="__main__"):

    print(entropy(1/3,2/3));