Middle three digits: Difference between revisions

</pre>

=={{header|Perl}}==

<lang Perl>#!/usr/bin/perl

use strict ;

use warnings ;

sub middlethree {

my $number = shift ;

my $testnumber = abs $number ;

my $error = "Middle 3 digits can't be shown" ;

my $numberlength = length $testnumber ;

if ( $numberlength < 3 ) {

print "$error : $number too short!\n" ;

return ;

}

if ( $numberlength % 2 == 0 ) {

print "$error : even number of digits in $number!\n" ;

return ;

}

my $middle = int ( $numberlength / 2 ) ;

print "Middle 3 digits of $number : " . substr( $testnumber , $middle - 1 , 3 ) . " !\n" ;

return ;

}

my @numbers = ( 123, 12345, 1234567, 987654321, 10001, -10001, -123, -100, 100, -12345 ,

1, 2, -1, -10, 2002, -2002, 0 ) ;

map { middlethree( $_ ) } @numbers ;

</lang>

{{out}}

<pre>Middle 3 digits of 123 : 123 !

Middle 3 digits of 12345 : 234 !

Middle 3 digits of 1234567 : 345 !

Middle 3 digits of 987654321 : 654 !

Middle 3 digits of 10001 : 000 !

Middle 3 digits of -10001 : 000 !

Middle 3 digits of -123 : 123 !

Middle 3 digits of -100 : 100 !

Middle 3 digits of 100 : 100 !

Middle 3 digits of -12345 : 234 !

Middle 3 digits can't be shown : 1 too short!

Middle 3 digits can't be shown : 2 too short!

Middle 3 digits can't be shown : -1 too short!

Middle 3 digits can't be shown : -10 too short!

Middle 3 digits can't be shown : even number of digits in 2002!

Middle 3 digits can't be shown : even number of digits in -2002!

Middle 3 digits can't be shown : 0 too short!