Comparing two arrays to see if identical

[mountainbiker]

Lets say we have 5 arrays, i.e.,

@a1, @a2, @a3, @a4, and @a5

Each array contains a list of path/filename. Each array is sorted, so if arrays are the same each corresponding element are the same, e.g.,

$a4[1] eq $a5[1], $a4[2] eq $a5[2], and so on.

Problem:
I want to compare each array against the other, so I keep only one copy. The copy I want to keep has the higer number in its array name. For example,

if @a1, @a3, and @a5 are identical and @a2 and @a4 are identical--I would be left with @a4 and @a5. (The other arrays can just be set to ().)

 

[mountainbiker]

How about something like this?

@arraynames = qw(a1 a2 a3 a4 a5);

@a1 = qw(1 2 3 4 5);
@a2 = qw(1 2 3 4 5 6);
@a3 = qw(1 2 3 4 5 6);
@a4 = qw(1 2 3 4 5);
@a5 = qw(1 2 3 4 5);

print "a1=@a1\na2=@a2\na3=@a3\na4=@a4\na5=@a5\n";

foreach $a ( @arraynames ) {
foreach $b ( @arraynames ) {
next if ($a eq $b);
@{$a} = () if ( compare_arrays( \@{$a}, \@{$b} ) );
}
print "\n";
}

print "a1=@a1\na2=@a2\na3=@a3\na4=@a4\na5=@a5\n";

sub compare_arrays {
my ($first, $second) = @_;
no warnings; # silence spurious -w undef complaints
return 0 unless @$first == @$second;
for (my $i = 0; $i < @$first; $i++) {
return 0 if $first->[$i] ne $second->[$i];
}
return 1;
}