program NOMURA2020A
    implicit none
    integer(8)::i,tlen
    character(200000)::T
    read*,T
    tlen=len_trim(T)

    do i=1,tlen
        if(T(i:i)=="?")then
            T(i:i)="D"
        end if
    end do
    print'(A)',T(1:tlen)
end program NOMURA2020A