c     examples/iter/iter_seq
c
      integer n,n3,iroot
      real*8 a(4,4),a1(4),b(4,4),x(4),c(4),tmp(4),y(4),tmp1
c     
c
      open(8,file='in.dat',status='unknown')
      read(8,*) n
      do i=1,n
         read(8,*) (a(i,j),j=1,n)
	 write(*,*) (a(i,j),j=1,n)
      enddo
      read(8,*) (c(i),i=1,n)
      write(*,*) (c(i),i=1,n)
      do i=1,n
         x(i)=1.
         y(i)=0.
      enddo
      diff=10.
      icount=1
      do while(diff.gt.1.e-8)
         do i=1,n
            write(*,*) 'i=',i,'  x=',x(i),'  y=',y(i)
         enddo
         do i=1,n
            y(i)=x(i)
         enddo
         do i=1,n
            tmp1=0.0
            do j=1,n
               if(i.ne.j) then
                  tmp1=tmp1+a(i,j)*y(j)
               endif
            enddo
            x(i)=(c(i)-tmp1)/a(i,i)
            write(*,*) 'i=',i,'  c=',c(i),'  tmp1=',tmp1
         enddo
         diff=0.
         do i=1,n
            diff=diff+dabs(y(i)-x(i))
         enddo
         icount=icount+1
         write(*,*) 'iter=',icount,'  diff=',diff
      enddo
      write(*,*) 'x(1)=',x(1),'  x(2)=',x(2),'  x(3)=',x(3)
      do i=1,n
         tmp(i)=0.0
         do j=1,n
            tmp(i)=tmp(i)+a(i,j)*x(j)
         enddo
      enddo
      write(*,*) tmp(1),tmp(2),tmp(3)
      stop
      end