program xsw

      character*80 lin, eof

      eof='EOF'


 10   read (5,100) lin
 100  format (a80)

      do 200 i=1,80
         if (lin(i:i).eq.'x') then
            lin(i:i) = lin(i-1:i-1)
            lin(i-1:i-1) = '^'
         end if
 200  continue

      write (6,100) lin

      if (.not.lin.eq.eof) goto 10

      end