Perl

In this article we learned how to sort strings or arrays of numbers in Perl. Perl has a built-in function called sort. There is no doubt that you can sort an array. The simplest form is to pass an array that returns an array of sorted elements.

One, List A list is a sequence of values enclosed in parentheses that can be any value or NULL, such as: (1, 5.3, "Hello", 2), empty list: (). Note: A list containing only one numeric value (for example: (43.2)) is different from the value itself

Sort by Requirement: Copy Code code as follows: #!/bin/perl @number =QW/5 10 15 3 2 4 8 6/;My @descending =sort {$a $b} @number; #这里 $a = 10, because $a was previously, the result of Perl was decimal in the previous, or ascending order.

The Perl programming language has a history of more than 26 years. December 18, 1987 Larry Wall introduced the Perl programming language, and the first post to quote the language was in 88 January, from Google's discussion group: Perl, a

[Email protected] ~]# wget http://www.cpan.org/src/5.0/perl-5.26.1.tar.gz[Email protected] perl-5.26.1]# cd/usr/local/[Email protected] perl-5.26.1]# tar zxvf/root/perl-5.26.1.tar.gz[Email protected] local]# CD PERL-5.26.1/[Email protected] perl-5.26

DBI: an APIthat connects all databases.DBD: is the DBI drive for different databases.Dbd::mysqlDBD::P GDbd::sqliteIf not , install with cpan .######################################################################DBI Interface:Customary

To re-assign each array element with a For loop:#!/usr/bin/perl@array = (1..30);p rint "@array \ n"; for ($i =0; $i Re-assigns each array element with a while loop:#!/usr/bin/perl@array = (1..30), $count = 1;print @array, while ($count Re-assigning

Python syntax is simple, and by indenting the way to express hierarchy, the code is very concise and easy to understand, for beginners, it is easier to get started.The pattern matching of Perl is very powerful, and there are many kinds of matching

Read standard input: in Perlforeach () {print "I saw $_";}The diamond operator <>: Its parameters are derived from the @argv array.The @argv array is checked first, and if it is empty, it is entered from the standard input stream. The value of the

Input and output: operator: Used to read data from STDIN:If you read the end of the file, the line input will return undef.$line = ; #读取下一行.Chomp ($line =); #去掉输入的一行的最后的换行符while () {print "$_";}foreach () {print "$_";}print function: used to output

You can decide if make the output shown on command screens by using 2>&1 or NULTesting script:print "without null \ n";System ("dir 2>&1");print "with null \ n";System ("dir > NUL");print "End \ n";Result:C:\rebecca\script\perl\unicode>perl

I. Condition statements:There are several types 1. If (condition expression) {statement block} 2. Single Perl statement if (conditional expression ); 3. If (condition expression) {statement Block 1} Else {statement Block 2} 4. If (condition

1. command line parameters in Perl: Perl provides a special built-in array @ argv to store user input parameters from the command line. The function is the same as the command line parameters of C/C ++, but the implementation is not the same; the

In addition to alternative list implementations, the Library also offers other tools such asBisectModule with functions for manipulating sorted lists: >>> Import bisect >>> scores = [(100, 'perl '), (200, 'tcl'), (400, 'lua'), (500, 'python')]>

#! C:/perl64/bin/perlRequire lwp: useragent; My $ UA = lwp: useragent-> new;$ UA-> timeout (10 );$ UA-> env_proxy; My ($ url_new, $ url_old) = @ argv;My $ response = $ UA-> get ($ url_new );Die $ response-> status_line unless ($ response->

Perl contains some predefined file handles. Such as standard input stdin, standard output stdout, and standard error stderr. The standard error stderr is an additional output path. How can we understand this sentence? Let's look at an example.% Perl-

1) grep function grep has two expressions: grep block listgrep expr, listblock represents a code block, usually represented by {}; expr represents an expression, usually a regular expression. In the original article, expr is anything, including one

Normal 0 7.8 磅 0 2 false false false MicrosoftInternetExplorer4 classid="clsid:38481807-CA0E-42D2-BF39-B33AF135CC4D" id=ieooui>st1/:*{behavior:url(#ieooui) }--> /* Style Definitions */

Network programming is a mysterious and complex art, and of course it is also very interesting. The PERL language provides a wide range of TCP/IP network functions, all of which are directly derived from the C language socket library

1. Question 2. Code and Output1 #-----------------------------------------------------------# 2 # Source: Learning Perl, chapter9, exercise-1 3 # Date: 2012-01-19 4 # Author: xiaodongrush 5 #---------------------------------------------------------