program newt_main
      implicit none
      integer n,i,i_again
      parameter (n=2)
      real x(n)
      logical check

 100  write(*,*) 'Type in the vector x(1:',n,') as initial guess :'
      read (*,*) (x(i),i=1,n)

c "n" is used to declare x(n) in subroutine newt, we therefore need
c  to make "n" an parameter in the main program.
      call newt(x,n,check)

      write(*,*) 'The resulting root vector is :'
      write(*,*) (x(i),i=1,n)

 102  write(*,*) 'Find root again ? (1=YES; 0=NO)'
      read(*,*) i_again
      if (i_again.eq.1) goto 100
      if (i_again.ne.0) goto 102

      end



c     subroutine funcv(n,x,f)
c     integer n
c     real x(n),f(n)
c     f(1) = x(1)**2 + x(2) - 1
c     f(2) = x(2)
c     end


c     subroutine funcv(n,x,f)
c     integer n
c     real x(n),f(n)
c     f(1) = x(1)
c     f(2) = x(2)
c     end

      subroutine funcv(n,x,f)
      integer n
      real x(n),f(n)
      f(1) = x(1)**2 + x(2)**2 - 25
      f(2) = x(2)
      end