subroutine computecfl(nx,ny,dx,dy,dt,cfl)
implicit double precision (a-h,o-z)
include 'rim2d.i'
ame=0.d0
do j=1,ny
do i=1,nx
c=sqrt(gamma(i,j)*p(i,j)/den(i,j))
ame=max(ame, max((abs(u(i,j))+c)/dx,(abs(v(i,j))+c)/dy))
cfl=ame*dt
enddo
enddo
return
end