Array Manipulation in Perl - A Difficult Assignment
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You can assign the elements of an array to scalar variables, as in the following example:


#!/usr/bin/perl 
# define array 
@human = ("John", "Doe"); 
 
# assign array contents to variables 
($fname, $lname) = @human; 
 
# print variables 
print ("My name is $fname $lname");



This won't work with an associative array, though - for that, you need the each() function. Every time each() runs on a hash, it creates an array containing two elements: the hash key and the corresponding hash value.


#!/usr/bin/perl 
# define hash 
%matrix = ("hero" => "neo", "villain" => "smith", "teacher" => "morpheus", "babe" => "trinity"); 
 
# get first pair 
($character, $name) = each (%matrix); 
print "$character = $namen"; 
 
# get second pair 
($character, $name) = each (%matrix); 
print "$character = $namen"; 
 
# and so on... 



The each() function comes in particularly handy when you need to iterate through an associative array, as it is well-suited for use in a "while" loop:


#!/usr/bin/perl 
# define hash 
%matrix = ("hero" => "neo", "villain" => "smith", "teacher" => "morpheus", "babe" => "trinity"); 
 
# iterate through hash with each 
# returns villain = smith hero = neo babe = trinity teacher = morpheus 
while (($character, $name) = each (%matrix)) 
{ 
        print "$character = $namen"; 
} 



You can assign the array itself to another variable, thereby creating a copy of it, as below:


#!/usr/bin/perl 
# define array 
@john = ("John", "Doe"); 
 
# copy array 
@clone = @john; 
 
# print copy 
print ("I am a clone named @clone"); 



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