program H2020A
    implicit none
    integer(8)::i
    integer(8)::flg=0
    character(10)::S
    read(5,*)S
    do i=1,len_trim(S),2
        if(S(i:min(len_trim(S),i+1))/="hi")then
            flg=1
            exit
        end if
    end do

    if(flg==0)print'(A)',"Yes"
    if(flg==1)print'(A)',"No"
end program H2020A