# num = 9 // 2
# print(num)name = "abcdefg"
“abcdefg” 字符串
“人” 字符
“人民” 人民 子字符串，子序列
ctrl + ?
# name = "abcdefg"
# if "人民" in name:
# print('OK')
# else:
# print('Error')
# if "人" not in name:
# if 1 == 1:
# if 2 > 2:
# if True:
# print('1')
# else:
# print('2')
# v = 1 == 2
# print(v)user = “salak”
pwd = “123”
#
v = user == ‘salak’ and pwd == “12” or 1 == 1 and pwd == “99854” and 1==2
print(v)
num = 123
v = num.upper()
print(v)
“”“
字符串
name1 = “shizhengwen”
v1 = name1.upper()
print(v1)
name2 = “LaiYing”
v2 = name2.upper()
print(v2)
“”“
整形， int
Python3里，1234123123123123123123123123123123123
Python2里，1234123112
长整形，long
Python2里，12341231124321342342 long
======== Python3 =========
整形 int
Python3里，1234123123123123123123123123123123123
a = 111
a.bit_length()
字符串 str
s1 = “salak”
s2 = “root”
s1.title()
s1.upper()
s1.startswith(‘xx’)
列表 list
元祖 tuple
字典 dict
布尔值 bool
a = “123a”
print(type(a),a)
#
b = int(a)
print(type(b),b)
num = “b”
v = int(num, base=16)
print(v)
age = 5
1 1
2 10
3 11
4 100
5 101
当前数字的二进制，至少用n位表示
r = age.bit_length()
print(r)
test = “salak”
首字母大写
v = test.capitalize()
# print(v)所有变小写，casefold更牛逼，很多未知的对相应变小写
v1 = test.casefold()
# print(v1)
# v2 = test.lower()
# print(v2)设置宽度，并将内容居中
20 代指总长度
* 空白未知填充，一个字符，可有可无
v1 = test.casefold()
# print(v1)
# v2 = test.lower()
# print(v2)去字符串中寻找，寻找子序列的出现次数
test = "salaksalakr"
v = test.count('ex')
print(v)# test = "salaksalakr"
# v = test.count('ex',5,6)
# print(v)
以什么什么结尾
以什么什么开始
test = "salak"
v = test.endswith('ex')
v = test.startswith('ex')
print(v)test = "salak"
v = test.endswith('ex')
v = test.startswith('ex')
print(v)从开始往后找，找到第一个之后，获取其未知
> 或 >=
test = "salaksalak"
未找到 -1
v = test.find('ex')
print(v)index找不到，报错 忽略
test = "salaksalak"
v = test.index('8')
print(v)格式化，将一个字符串中的占位符替换为指定的值
test = 'i am {name}, age {a}'
print(test)
v = test.format(name='salak',a=19)
print(v)test = 'i am {0}, age {1}'
print(test)
v = test.format('salak',19)
print(v)格式化，传入的值 {“name”: ‘salak’, “a”: 19}
test = 'i am {name}, age {a}'
v1 = test.format(name='df',a=10)
v2 = test.format_map({"name": 'salak', "a": 19})
字符串中是否只包含 字母和数字
test = "123"
v = test.isalnum()
print(v)