#既十进制数值用二进制表示时，最少使用的位数
i = 3#3的ASCII为：0000 0011，即两位

s = i.bit_length()

print(s)

while 1:

    print('all trule')

s = 'sdfjskjdfl'

print(s[0])

print(s[2])

print(s[0:2])

print(s[0:4:2])

print(s[:]) #取完

print(s[3:0:-1]) #倒着取，注意，3在0后，方向也必须反向

s = 'sdfjskjdfl'

s1 = s.capitalize()#字符串首字母大写

print(s1)

s = 'sdfSKFKKskdfjl'

s2 = s.swapcase() #大小写翻转

print(s2)

print('here you are'.title()) #每个单词的首字母大写

s = 'afsdf,fsdfsdf.sdf#fsdsg%fs456.2'

print(s.title())

print(''.center(20,'#')) #内容居中，根据长度进行填充，默认填充物是空格

print('name'.count('n')) #字符串中的元素出现的次数

print('name123name123name'.count('n',2,-1)) #可进行切片操作,想取到最后一位是：.count('str',start[int]),后面不要接end[int]就可以了

print('123\t456'.expandtabs())#将\t前面的补全，默认将一个tab键变成8个空格，补足为8位；若超8个，则补全16个，以此类推

print('ggasds'.startswith('g'))#判断是否以...开头

print('ggasds'.endswith('s'))#判断是否以...结尾

print('ggasds'.startswith('gg',0,4))#顾首不顾尾

print('ggasds'.endswith('ds',-3))#顾首不顾尾
print('ggasds'.endswith('ds',-3,-1))#顾首不顾尾

print('asdhjksdf'.find('dh',2,5))
print('asdhjksdf'.find('dh',1,3))
print('asdhjksdf'.find('xiao'))

print('asdhjksdf'.index('dh',2,5))

print('asdhjksdf'.index('xiao'))

print('sdfjskdfjsdfllj234j'.split('df'))#以什么进行分割，形成一个列表不包含此分割元素

s = 'title,Tilte,atre,'.rsplit('t',1)#从右边开始，只对第一个操作元素进行分割处理

print(s)

s = '''name:{}

age:{}

job:{}'''.format('kk',12,'stu')

print(s)

s = 'name:{0},age:{1},job:{2},full-name:{0},real-age:{1},present-job:{2}'.format('dd','','tea')

print(s)

s = 'name:{name},age:{age},job:{job},full-name:{name},real-age:{age},present-job:{job}'.format(age='',job='tea',name='dd')

print(s)#后面变量位置随意调动

print('    sfsfs   '.strip())#去除空格

print('***sdf****'.strip('*'))#去除*

print('    sdfdfsd****'.lstrip())#去除左边空格

print('    sdfdfsd****'.rstrip('*'))#去除右边*

print('%****&&12%*3%***'.strip('%*'))#只要左右两边出现包含在里面的任意一个字符，就去除

###遇到不是被去除的字符就终止

print('i have a dream'.replace('dream','apple'))#全局替换

print('i have a dream,i dream one day...'.replace('dream','apple',1))#只替换第一个匹配到的字符

print('name123'.isalpha())#只由字母组成

print('name123'.isdigit())#只由数字组成

print('name123'.isalnum())#由字母或数字组成

list1 = ['physics', 'chemistry', 1997, 2000]

list2 = [1, 2, 3, 4, 5 ]

list3 = ["a", "b", "c", "d"]
print(list1)
print(list2[2])
print(list3[0:3:2])#2是步长

tup1 = ('physics', 'chemistry', 1997, 2000)

tup2 = (1, 2, 3, 4, 5 )

tup3 = "a", "b", "c", "d"