basic networking fundamentals

it from the beginning, and move the cursor without using#F.flush (): Forces the contents of memory to be flushed to the hard disk, often for write-sensitive data such as amounts#when a refresh is not enforced, the system waits for a certain amount of data to be written to the hard disk when the memory is stored#Simulation Process BarImportSys, time forIinchRange (20): Sys.stdout.write (">") Sys.stdout.flush () Time.sleep (0.5)6. With statement: The file is automatically closed after execution i

odd pages even)//(divisible, returns the integer part of the quotient)Conditional operator: = = = = Assignment operator: = = = = *=/=%= **=//=Logical operators: And Or not (for example: not 1==1)Member operators: in Not IN (for example: if 1 in [1, 2, 3, 4])Identity operator: is isn't (for example: a=[1,2,3,4] If Type (a) is list:)Bitwise operators: (bitwise VS: AB) | (bitwise OR) ^ (bitwise XOR, XOR: Difference is 1, otherwise 0) ~ (bitwise Reversed) Ternary operators:A, B, C=1, 3, 5D=a if a>

is not secure, so sudo is a good choice)Modify configuration File command: VisudoInstallation method: Yum install-y sudoSyntax: sudo normal command inputConfiguration file:/etc/sudoers*****************************************************......Root all= (All) allEssence all= (Root)/bin/ls......**********************************************************The meaning is, let essence this ordinary user, have root permission, for LS this command. (To add absolute path OH)Security extensions/etc/ssh/ssh

, index, Elementdata, index + 1,6Size-index);//Copy only objects after the current position 7Elementdata[index] =element;8size++;9} Delete Object public E Remove (int index) {Rangecheck (index); Modcount ++; E oldValue = Elementdata (index); int nummoved = Size-index-1; if (nummoved > 0 +1, Elementdata, index, nummoved);// After setting the position of the object, move forward one elementdata[--size] = null ; // Let the GC do it work return

timer (func): #装饰函数#def Inner (*args):#start=time.time ()#Ret=func (*args) #被装饰函数#end=time.time ()#print (End-start)#return ret#return inner#@timer#def func (x):#time.sleep (0.01)#print ("haha hehe")#return x#Print (func ([up]))#Decorator with parameters and return values of any type#def timer (func): #装饰函数#def Inner (*args,**kwargs):#start=time.time ()#Ret=func (*args,**kwargs) #被装饰函数#end=time.time ()#print (End-start)#return ret#return inner#@timer#def func (x, y):#time.sleep (0.01)#print ("h

The floating-point literal defaults to a double type, so adding F or f;double type after the defined float data is not a suffix, but be sure to write D or x.x float in the decimal calculation The accuracy is not long and the number of significant digits (Mantissa) is short. The range of float is larger than the long index can be large. Floating-point numbers are imprecise and cannot be accurately compared to floating-point numbers.3) a character type (char): Char:16 bit, is an integer type, 1

mouse button, the effect is in the desktop or folder in the blank space right click, will appear "open from terminal" shortcut. That requires the use of a software.The installation is simple, open the terminal, enter inside: sudo apt-get install nautilus-open-terminal Copy CodeThe shortcut is then automatically added to the right-click.4.ctrl+alt+t, shortcut key is doneSecond, network restart:After we have configured the network information, and do not want to restart Linux, how t

course, is not beyond the floating point of the effective bit can not be accurately expressed, in fact, the main thing is the most effective bit and the lowest non-0 effective bit between the "gap", if the gap in the floating point of the significant number of digits, the natural can be accurately expressed, because the lower effective bit of the shed is 0, naturally does not matter If the floating-point type of the above example uses a double, the precision is not lost because the double has a

direct conversionIntLongFloatDoubleBoolean (itself True/false only two values, so no other type can be converted)Char (Char's particularity makes char unable to use other conversions)One can see the difference1. In addition to the other types of char can be converted from small to large, the view period source code is inherited, implemented the following ways？ extendsimplementsHave inherited the number class. Which is the digital type.2.char different from other data types The reason is also h

/dir=================================================================================[[emailprotected] ~]#stattest11.gzfile: ' test11.gz ' Size:122 Blocks:8 ioblock:4096regularfiledevice:802h/2050d Inode:12133Links: 1access: (0644/-rw-r--r--) Uid: (0/root) Gid: (0/root) access:2015-03-10 14:50:52.616930866+0800Modify:2015-03-0505:30:10.555977000+0800Change: 2015-03-1014:50:44.910931488+0800================================================================= ================PS: Changing CTime does n