#!perl s!!- !;eval's/./$& $&/g;'x+pop;print
#!perl s!!- !;for$"(1..pop){s/./$& $&/g}print
#!perl s//- /;for$a(1..pop){s/./$& $&/g}print
#!perl s//- /;s/./$& $&/gwhile$ARGV[0]--;print