real y(2),work(15),mass
	integer iwork(5)
	common  g,arhim,alpha
	external f
	data pi/3.1415926536/
	open (10,file='fall.in')
	open (20, file='fall.out')
	neqn=2
	read(10,*)dt,nt,relerr,abserr,y,r,g,rov,rok,etta
	mass=4.*pi*r**3*rok/3.
	arhim=rov*g/rok
	alpha=6.*pi*etta*r/mass
	
	print *,relerr,abserr,dt,nt,y,r,g,roa,rok,etta
	print *,mass,arhim,alpha
	talg=0
	tlopp=0
	iflag=1
	call rkf45(f,neqn,y,talg,tlopp,relerr,abserr,iflag,work,iwork)

	do i =1,nt
	tlopp=talg+dt
	iflag=2
	call rkf45(f,neqn,y,talg,tlopp,relerr,abserr,iflag,work,iwork)
	talg=tlopp
	write(20,100) tlopp,y(2)
100	format(6f15.5)
	enddo
	stop
	end
	
	subroutine f(t,y,dy)
	real y(2),dy(2)
	common  g,arhim,alpha
	dy(1)=y(2)
	dy(2)=g-arhim-alpha*y(2)
	return
	end