I was playing with this a bit, since it's such a fun little problem. Here's a version that returns the answer as the value of the function. 

#!/usr/bin/perl

# http://perlmonks.org/?node_id=1211497

use strict;
use warnings;

sub up
  {
  my ($row, $col) = split /-/, $_[0];
  return $_[0] eq '0-0' ? "@_\n" :
    ($row * $col > 0 && up( ~-$row . '-' . ~-$col, @_ ) ) .
      ($row > $col && up( ~-$row . '-' . $col, @_ ) );
  }

print up( '3-1' );

[download]

It's only a two statement function (of course one statement is very long :)

In reply to Re: compute paths in Pascal's triangle (aka Tartaglia's one) by tybalt89
in thread compute paths in Pascal's triangle (aka Tartaglia's one) by Discipulus

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