#!/usr/bin/python

# -*- coding: UTF-8 -*-

#by ZhiQiang Zhao  email:ZhiqiangZhao55@163.com

import os

file=open("./bandstructure.txt",'r')

K=open('./out.txt','w') 

a=0

b=input("interval:")  #以多少为间隔提取数据

while True:

a+=1

line=file.readline()

arr=line.split()

if(line!=''):

if(a==1):

x=float(arr[0])

K.writelines('{0:.8f}'.format(x)+'\n')

elif(a%b==0):

y=float(arr[0])

K.writelines('{0:.8f}'.format(y)+'\n')

else:

continue

else:

break

bands.py