Summary of Python basic operations
Variable naming
Variable names can only be a combination of letters, numbers or underscores
The first character of the variable name cannot be a number
You cannot use some reserved keywords, such as and, as, assert, break, etc.
Officially recommended method name_of_BF
Python There is no constant statement, it is recommended to express constants in all uppercase letters
Characters
## Development History: ASCII - > GB2312 -> GBK1.0 -> GB18030 (PC must support , General mobile phones only support GB2312) -> UNICODE (Two bytes for all identifiers) -> UTF-8 (Variable length encoding, one byte for English, three bytes for Chinese)
Python2.X Does not support Chinese characters, you need to declare the character set first
# -*- coding:utf-8 -*-##Python3.X Direct supportUNICODE, so you can directly use Chinese
## without declaring a character set-
Comment
Comment Multi-line: Three single quotes
-
#Console input
##username =
("username:") password=input("password:") ##Python 2.x raw_input Equivalent to 3.x input #input in ##2.x , will be regarded as the input format, so try not to use For example: when entering will find the variable ## of alex #Input in 3.x, will be treated as STRING Print multiple lines: three single quotes info='''name:''' '''password:'''+passwordinfo2 =''' name:{_name}##password:{_password} ''' _name=username _password=password) info3=''' name:%s password:%d '''%(username,password) ##info4 =''' name:{0} .format(username,password) The official recommendation is to use the second one password protection getpass input( "username:")##password=getpass.getpass( ) Note: PYCHARM . CMD里中用PYTHON好用 ##judge :print ( ) elif guess_age>_age_of_jason: ##print(" thinksmaller...") #else: ("thinkbigger...") ##Python Forces indentation, so no closing character is required cycle guess_age= (input("Jason'sage:"))##ifguess_age==_age_of_jason: print( )##break elifguess_age>_age_of_jason: print("thinksmaller..." elifguess_age<_age_of_jason: print( "thinkbigger..." ##counter=counter+1 ifcounter==3: print("nochanceanymore...") break whilecounter<3: guess_age=int(input("Jason'sage:")) if guess_age==_age_of_jason: print("bingo") break elifguess_age>_age_of_jason: print("thinksmaller...") elifguess_age<_age_of_jason: print("thinkbigger...") counter=counter+1 else: print("triedtoomanytimes,fuckoff") for i in range(0,3): guess_age=int(input("Jason'sage:")) if guess_age==_age_of_jason: print("bingo") break elif guess_age>_age_of_jason: print("thinksmaller...") elif guess_age<_age_of_jason: print("thinkbigger...") else: print("triedtoomanytimes")
'''Print Single line: a double quote "
##String concatenation
+
import
_age_of_jason
:
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