#!/usr/bin/perl 
sub print_coor{ 
    my ($x,$y,$z) = @_; 
    print "$x $y $z \n"; 
    return $x;
}; 
$k = 1; 
$j = 2; 
$m = 4; 
$this = print_coor($k,$j,$m); 
$that = print_coor(4,5,6);