@x = (0, 18, 36, 0, 18, 36, 0, 18, 36, 0, 18, 36, 0, 18, 36, 0, 18, 36
+);
@y = (0, 0, 0, 18, 18, 18, 36, 36, 36, 0, 0, 0, 18, 18, 18, 36, 36, 36
+);
@z = (25, 25, 25, 25, 25, 25, 25, 25, 25, 20, 20, 20, 20, 20, 20, 20, 
+20, 20);

@reindex = sort { $z[$a] <=> $z[$b] || $x[$a] <=> $x[$b] } 0..$#x;
@x=@x[@reindex];
@y=@y[@reindex];
@z=@z[@reindex];

use Data::Dumper;
print Dumper \@x;
print Dumper \@y;
print Dumper \@z;
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