UNIX for Dummies Questions & Answers

How can I use Perl to a take a string of 10 characters and print the last five characters of the string in columns 1-5 and the first five in columns 6-10?

Result:
0123456789

5 0
6 1
7 2
8 3
9 4

If the string is a constant and the output is also constant, use 'substr' to put each character into variables then print out in any format you want.

Code:

my $first_char = substr $_, 0, 1;
my $second_char = substr $_, 1, 1;
my $third_char = substr $_, 2, 1;
my $fourth_char = substr $_, 3, 1;
.
.
.
print "$sixth_char\t$first_char\n";
print "$seventh_char\t$second_char\n";
.
.
.
and so on

Code:

$ echo 0123456789 | perl -nle 'for ($i=0; $i < 5; $i++) { print substr($_,$i+5,1)," ", substr($_,$i,1) }' 
5 0
6 1
7 2
8 3
9 4

The string is actually going to be coming from STDIN.

So I dug around and found some code similar to what I want, but not quite (similar in that it can break a string down by characters).

#!/usr/bin/perl
print "Enter 10 characters\n";
chomp ($foo=<STDIN>);
{
%seen = ();
foreach $char (split //, $foo) {
$seen{$char}++;
}
print "broken into columns: ", sort(keys %seen), "\n";
}
print $foo;

How can I get this to print characters into columns then?

Nevermind. Got it.

#!/usr/bin/perl
print "Enter 10 characters\n";
chomp ($foo=<STDIN>);
@arr=split //, $foo;
for($i=0;$i<5;$i++) {
print $arr[$i+5] . " " . $arr[$i] . "\n";
}