@original= (0 .. 5);
@true = grep $_*=2, @original;
local $" = ", ";  # for nicely formatted output
print "original: @original\n";
print "output: @true\n";

##</code><code>##

original: 0, 2, 4, 6, 8, 10
output: 2, 4, 6, 8, 10