program sample
    implicit none
    
    integer(8) :: a,b,c,i,j,m,n,k,a1,b1,c1
    integer(8), allocatable  ::x(:) 

    read(*,*) n
    k=6
    do while(n<2**k)
        k=k-1
    end do
    write(*,*)2**k
    
    stop
end program sample
  

