Samy_rio has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks, I have some problem in number ranges.

I have tried the following coding, its working fine for three digit ranges (123-135) but it may vary in number of digits(12-14, 1234-1256).

use strict;

my $a="123-135, 111-119, 127-130, 140-145";
print "Original : $a\n";

my @a = split (/\, /, $a);
eval{s/^(\d{2})(\d+)\-(\d{2})(\d+)$/&digit($1,$2,$3,$4)/egsi;} for (@a
+);

print "Changed  : ";
print "$_\t" for @a;

sub digit{
    my ($f, $f1, $s, $s1)=@_;     
    if ($f == $s){
        $s=$s1;
    }
    else{
        $s=~s/\d//; $s.=$s1;
    }        
return qq($f$f1-$s);
}

[download]

But when i get the input like this, the above coding not works, is there any other way to do?

my $a="9-35, 11-19, 1272-1340, 1430-1435";

Is there any module?

Regards,
Velusamy R.

Replies are listed 'Best First'.
Re: Problem in Number Range
by jasonk (Parson) on Oct 03, 2005 at 15:10 UTC

    Is there any module?

    Yep, try Set::IntSpan.

    We're not surrounded, we're in a target-rich environment!
[reply]
Re: Problem in Number Range
by ikegami (Patriarch) on Oct 03, 2005 at 15:28 UTC

    I'm nto sure what you are trying to do. If you're trying to extract the numbers, how about:

    $str = "123-135, 111-119, 127-130, 140-145";
@nums = split(/\s*[-,]\s*/, $str);

    [download]

    or if you want to keep the pairs together:

    $str = "123-135, 111-119, 127-130, 140-145";
@nums = map { [ split(/-/, $_) ] } split(/\s*,\s*/, $str);

    [download]

    Neither of the above validates. They assume the input is in the appropriate format.

[reply]
[d/l]
[select]
Re: Problem in Number Range
by InfiniteSilence (Curate) on Oct 03, 2005 at 16:03 UTC
    The problem is in the algorithm. Assuming that a<b: 

    #!/usr/bin/perl -w
use strict;

my $str = $ARGV[0]||"123-135, 111-119, 127-130, 140-145";
#borrowed from ikegami
print "Original string \n" . $str;
print "\nEnding string \n";
print show($_) for map { [ split(/-/, $_) ] } split(/\s*,\s*/, $str);

sub show {
    my (@anums) = split //,$$_[0];
    my (@bnums) = split //,$$_[1];
    my ($output) = $$_[0] . '-';
    my $switch = 0;
    if ($#anums != $#bnums){
        return $$_[0];
    }
    for(0..$#bnums){
    if(defined($anums[$_])){
          #if same, do nothing
      #if larger, include
        if (($bnums[$_] > $anums[$_])|| ($switch)){
        $output .= $bnums[$_];
                $switch++;
            }
        } 
    }
    return $output . ' ';
}

    [download]

    Celebrate Intellectual Diversity

[reply]
[d/l]
Re: Problem in Number Range
by cognizant (Pilgrim) on Oct 03, 2005 at 15:30 UTC
    Try this 
    use strict;

my $a="123-135, 1-119, 1270-1280, 1420-1452";
print "Original : $a\n";

my @a = split (/\, /, $a);
eval{s/^([0-9]*)([0-9]+)\-([0-9]*)([0-9]+)$/&digit($1,$2,$3,$4)/egsi;}
+ for (@a);

print "Changed  : ";
print "$_\t" for @a;

sub digit{
    my ($f, $f1, $s, $s1)=@_;
my ($fs, $se);
    if($s =~ /([0-9]+)([0-9])/)
   {
        $fs = $1; $se = $2;
   }
    if ($f == $s)
    {
        $s=$s1;
    }
    elsif($f=~/^$fs/)
    {
        $s=$se.$s1;
    }
        
    else{
        $s=~s/\d//; $s.=$s1;
    }        
return qq($f$f1-$s);
}

    [download]
[reply]
[d/l]

      Here, i am getting output as

      Changed  : 123-35       1-19     1270-80 1420-52

      instead of

      Changed  : 123-35       1-119     1270-80 1420-52

      That is, "1-119" is a correct range, but its changed as "1-19". This case happening in all correct ranges like "1-10" also.

      Regards,
      Velusamy R.

[reply]
[d/l]
[select]
        Modify the last snipped of the code as follows: 
            else{
        #$s=~s/\d//;
        $s.=$s1;
    }

        [download]
[reply]
[d/l]

Back to Seekers of Perl Wisdom