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

import pandas as pd
import numpy as np

student1=pd.Series({'국어':np.nan,'영어':80,'수학':90})
student2=pd.Series({'수학':80,'국어':90})

print(student1)
print('\n')
print(student2)
print('\n')

sr_add=student1.add(student2,fill_value=0)
sr_sub=student1.sub(student2,fill_value=0)
sr_mul=student1.mul(student2,fill_value=0)
sr_div=student1.div(student2,fill_value=0)

result=pd.DataFrame([sr_add,sr_sub,sr_mul,sr_div],index=['덧셈','뺄셈','곱셈','나눗셈'])

print(result)