program main
	implicit none
	integer :: N, S, i
		read(*,*) N
		S=1000
		if(N<=1000)	then
			write(*,*) S*1-N
		else if(1000<N .and. N<=2000) then
			write(*,*) S*2-N
		else if(2000<N .and. N<=3000) then
			write(*,*) S*3-N
		else if(3000<N .and. N<=4000) then
			write(*,*) S*4-N
		else if(4000<N .and. N<=5000) then
			write(*,*) S*5-N
		else if(5000<N .and. N<=6000) then
			write(*,*) S*6-N
		else if(6000<N .and. N<=7000) then
			write(*,*) S*7-N
		else if(7000<N .and. N<=8000) then
			write(*,*) S*8-N
		else if(8000<N .and. N<=9000) then
			write(*,*) S*9-N
		else if(9000<N .and. N<=10000) then
			write(*,*) S*10-N
		endif
end program main