# -*- coding: utf-8 -*-
#print absolute value of an integer:
# a = raw_input('請輸入a的值：'.decode('utf-8').encode('gbk'))
# a = int(a)
# if a >= 0:? #使用“：”冒號并配合縮進(jìn)來表示代碼塊
# print a
# else:
# print -a
# print u'測試中文輸出'
# ##=================================================================
# #測試占位符
# print 'ENGname:%s CHNname:%s Age:%d salary:%d' %('ArmedYang',u'楊', 21, 1111)
# ##=================================================================
# #測試list使用
# workmates = ['sunjiayao','dufen','wangxianyuan','lidongyang','dingxuyong','zhoufeng','zhangchen']
# a = len(workmates)
# print a
# print 'first mate'
# print workmates[0]
# print 'last mate'
# print workmates[-1]
# print 'add new mate'
# workmates.insert(0,'yangjiahui')
# workmates.append('somebodyelse')
# print 'show new group'
# print workmates
# print 'remove somebody'
# print workmates.pop(-1)
# a = len(workmates)
# print a
# workmates.append(['teacher ai','teacher chen'])
# print 'the teacher of this group is %s and %s' %(workmates[-1][0],workmates[-1][1])
# for mate in workmates:
# print mate
# ##=================================================================
# #測試tuple使用
# workleader = ('chen','ai',[])
# ###workleader.append is forbidden since its a tuple and cannot be modified,but workleader[2] is an empty list which can be modified
# workleader[2].append('leader1')#append takes exactly one arguement
# for leader in workleader:
# print leader
# ##=================================================================
# #測試死循環(huán)drop-dead
# a = range(5)
# print a
# b = raw_input('press any key to get start this endless loop')
# while a:
# print 'im drop deading'
# ##=================================================================
# #測試dict和set
# holiday = {'spring fes':101, 'fool\'s day':401, 'children\'s day':601,}
# print holiday['spring fes']
# print 'my birth' in holiday
# print holiday.get('my birth','not exist')
# holiday['my birth'] = 1207
# print holiday.get('my birth','not exist')
# holiday.pop('fool\'s day')
# print holiday
# week = set(range(1,8))
# print week
# week.add(7)
# #when add a element already exist,the set wont change
# print week
# workday = week.copy()#create a copy of set week
# #and workday = week won't work since when you modify workday will also change week
# weekend = set([6,7])
# for zhoumo in weekend:
# if zhoumo in workday:
# workday.remove(zhoumo)
# print workday
# print week
# print week == (workday | weekend)
import math
print math.pi
