qr/^(.)
(?!\1)(.)
(?!\1)(?!\2)(.)
(?!\1)(?!\2)(?!\3)(.)
(?!\1)(?!\2)(?!\3)(?!\4)(.)
(?!\1)(?!\2)(?!\3)(?!\4)(?!\5)(.)
\1
$/x
swipe's
enforce
tugboat
discard
slogans
sailors
neutron
shock's
singles
snipe's