#!/usr/bin/perl
use strict;
use warnings;

my @nodes= qw(A B C D E F G H I J);
my %edges= (
    A => [qw(B C F I D G J E)],
    B => [qw(A C D E F H J I)],
    C => [qw(A B D E F I)], 
    D => [qw(A C B E G J)], 
    E => [qw(A D C B G H I J)], 
    F => [qw(B C A H J I)], 
    G => [qw(D A E H I J)], 
    H => [qw(F B G E I J)], 
    I => [qw(B F C A H G E J)], 
    J => [qw(E G D A H F B I)], 
    );
my @lines=(
        [qw(A C F I)],
        [qw(A D G J)],
        [qw(B C D E)],
        [qw(B F H J)],
        [qw(E G H I)],
        );

my $lines= join("\n", map join(" ", sort @$_),@lines);

my %triangle;

foreach my $a (@nodes) {
    foreach my $b (@{$edges{$a}}) {
        foreach my $c (@{$edges{$b}}) {
                        next if $c eq $a;
                        foreach my $d (@{$edges{$c}}) {
                                next if $d eq $b;
                                next unless $d eq $a;
                                my $triangle= join(' ', sort($a, $b, $
+c));
                                my $re= join(' (\S+ )*', sort($a, $b, 
+$c));
                                next if $lines=~ /$re/;
                                ++$triangle{$triangle};
                        }
                }
     }
}
print join("\n", scalar keys %triangle, sort keys %triangle),"\n";
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