I found a problem where I get a different result when printing an array after calling a function, that shouldn't be able to change the array. I got the issue down to this:

use strict;
use warnings;

main();

sub main {
    problem([[0,1,2],[3,4,5],[6,7,8]]);
}

sub problem {
    print3DArray("\@_",@_);#Output: 0 1 2 3 4 5 6 7 8
    reverseArray(@_);
    print3DArray("\@_",@_);#Output: 6 7 8 3 4 5 0 1 2
}

sub reverseArray {
    for(my $i=0;$i<scalar(@_);$i++){
        @{$_[$i]} = reverse @{$_[$i]};
    }
}

sub print3DArray {
    print shift @_, ":\n";
    for(my $i=0;$i<scalar(@_);$i++){
        print2DArray(@{$_[$i]});
    }
}

sub print2DArray {
    for(my $i=0;$i<scalar(@_);$i++){
        for(my $j=0;$j<scalar(@{$_[$i]});$j++){
            print $_[$i][$j]," ";
        }
        print "\n";
    }
    print "\n";
}
[download]

@_ should stay the same, since I didn't return anything. I would appreciate any help! Thanks!

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