Re: help writing simple perl script

Here is some simple code to do it. Put it in a file and redirect the output to list.txt (e.g. foo.pl>list.txt).

use strict;
my @arr = <STDIN>;
map chomp $_, @arr;
foreach my $i (0..$#arr){
    foreach my $j (0..$#arr){
        print "$arr[$i] $arr[$j]\n" if $i != $j;
    }
}
[download]

Smaller versions surely exist...

Update: If you want to read from list.txt use

foo.pl<list.txt

Comment on Re: help writing simple perl script Select or Download Code

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Re^2: help writing simple perl script by ashylarry (Initiate) on Jul 27, 2006 at 20:06 UTC
Actually this one almost gets me all the way there, but ends up printing out a lot of redundancy. I only want any given pair of numbers to appear only ONCE in the output (regardless of the order). In other words, for 4 numbers, instead of: 1 2 1 3 1 4 2 1 2 3 2 4 3 1 3 2 3 4 4 1 4 2 4 3 ...I'd want the output to be: 1 2 1 3 1 4 2 3 2 4 3 4 Is there a way to do this without using the Math::Combinatorics module (I don't have permissions to install Perl modules, and hate having to go through our IT admin, so would like to avoid this if possible)	[reply]
Re^3: help writing simple perl script by traveler (Parson) on Jul 27, 2006 at 20:23 UTC
Ahh, ok, different problem. Just change the inner loop to `foreach my $j ($i..$#arr){` [download]	[reply] [d/l]
Re^2: help writing simple perl script by ashylarry (Initiate) on Jul 27, 2006 at 16:50 UTC
awesome! This one works great. Thanks so much!	[reply]