Locate a substring with space inside

     
#!/usr/bin/perl -w

use strict;

$_ = "a Aa aA AaA aA A";

if (/a a/) {
    print "found\n";
}

1.	Get the sub string
2.	Using substr with offset (-6) and length (-2)
3.	Using substr with offset (-6), and length (2)
4.	Using substr with the string and the offset (2)
5.	Using substr with the string, offset (2) and length (3)
6.	substr and index function
7.	substring from 10 to 14
8.	Find the substring with '$_ =~ /Aa/'
9.	Using substr.
10.	If the offset is negative, substr counts from the end of the string

Locate a substring with space inside : substr « String « Perl