program main
    implicit none
    integer(8):: n,i,j,answer=0
    integer,allocatable,dimension(:)::a,b
    read(*,*)n
    allocate(a(0:n),b(0:n))
    read(*,*)a
    read(*,*)b
    do i=0,n
       answer=answer+(sum(a(0:(n-i)))*b(i))
       answer=mod(answer,1000000000+7)
    enddo
    write(*,*)answer
end program main