program main
implicit none
integer :: sx, sy, tx, ty
character :: root*32004
integer :: i, j 

read(*,*) sx, sy, tx, ty
do i = 1, 32004
   if ( i .le. tx - sx ) then
      root(i:i) = 'R'
   else if ( i .gt. tx - sx .and. i .le. tx+ty-sx-sy ) then
      root(i:i) = 'U'
   else if ( i .gt. tx+ty-sx-sy .and. i.le. 2*tx+ty-2*sx-sy ) then
      root(i:i) = 'L'
   else if ( i .gt. 2*tx+ty-2*sx-sy .and. i.le. 2*tx+2*ty-2*sx-2*sy+1 ) then
      root(i:i) = 'D'
   else if ( i .gt. 2*( tx+ty-sx-sy )+1 .and. i.le. 3*tx+2*ty-3*sx-2*sy + 1 ) then
      root(i:i) = 'R'
   else if ( i .gt. 3*tx+2*ty-3*sx-2*sy + 1 .and. i.le. 3*(tx+ty-sx-sy) + 1 ) then
      root(i:i) = 'U'
   else if ( i == 3*( tx+ty-sx-sy ) + 2 ) then
      root(i:i) = 'L'
   else if ( i == 3*( tx+ty-sx-sy ) + 3 ) then
      root(i:i) = 'U'
   else if ( i .gt. 3*( tx+ty-sx-sy) + 3 .and. i.le. 4*tx+3*ty-4*sx-3*sy + 3 ) then
      root(i:i) = 'L'
   else if ( i .gt. 4*tx+3*ty-4*sx-3*sy+3 .and. i.le. 4*( tx+ty-sx-sy )+3 ) then
      root(i:i) = 'D'
   else if ( i == 4*( tx+ty-sx-sy+1 ) ) then
      root(i:i) = 'R'
   end if
end do
write(*,'(a)') root(1: 4*(tx+ty-sx-sy+1) )
end program main
