#!perl -l for$$(1..pop){$_.=$ARGV[1&grep$|<($$-=$_),/./g]}print
#!perl -l for$$(1..pop){$_.=$ARGV[1&grep 0<($$-=$_),/./g]}print
#!perl push@a,($j=$ARGV[$_&1])x($a[$_]||$j)for@b=0..-1+pop;print@a[@b],$/