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";$t=here;for$b(@B=qw(moo baa quack oink)){$@=&W." $b-$b ";print$_&&$/,$0="Old MacDonald had a farm$.","And on his farm he had a ",qw(cow pig duck sheep)[$_],"$.With $@$t, and $@t$t.
";"@B[-$_,~$_]"=~$",$@=&W.$".$`,print"\u$t $@, t$t $@, everyw$t $@-$`.
",$_?"A $'-$' $t, and a $'-$' t$t.
":$0for$_--..0}sub W{/3/?an:a}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).