program pairpair

integer::n,m,l=12,cnt=1
character(1),dimension(13)::a
character(13)::S
character(10)::Imp='Impossible'
read *,S

do n=1,13
 a(n)=S(n:n)
end do

do n=1,13
  do m=1,l
   if(a(n)==a(n+m)) then
    cnt=cnt+1
    if(cnt==3) exit
   end if
  end do
 if(cnt==3) exit
 cnt=1
 l=l-1
end do


if(cnt==3) then

 print *,Imp

else
 l=12
 do n=1,13
  do m=1,l
   if(a(n)==a(n+m)) then
    a(n)='#'
    a(n+m)='#'
   end if
  end do
 end do

 if(count(a(:)=='#')==12) then
  do n=1,13
   if(a(n)=='#') cycle
   print *,a(n)
  end do
 else
  print *,Imp
 end if

end if
end program pairpair