c----GRID GENERATOR PROGRAM----
        parameter (nx=11,ny=10,nne=(nx+2)*(ny+1))
        integer num(1:ny+1,0:nx+1)
        real x(nne),y(nne)
        real xp(nne),yp(nne)
        open(1,file='mesh.dat',status='unknown')
        open(2,file='number.dat',status='unknown')
        open(3,file='coord.dat',status='unknown')
c----parameters----
        xd=2.
        yd=1.8
        nxc=(nx+1)/2
        nyc=1
        y0=0.0
        x0=-xd/2.
        dy=yd/(ny-1)
        dx=xd/(nx-1)

c----parameters----
        do i=0,nx+1
        do j=1,ny+1
        num(j,i)=0
        enddo
        enddo
c----create 'E' boundary----
        iq=0
        xx=(0-nxc)*dx
        do i=1,ny
        iq=iq+1
        num(i,0)=-iq
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo

        yy=(ny+1-nyc)*dy
        do i=0,nx+1
        iq=iq+1
        num(ny+1,i)=-iq
        xx=(i-nxc)*dx
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo

        xx=(nx+1-nxc)*dx
        do i=ny,1,-1
        iq=iq+1
        num(i,nx+1)=-iq
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo
        ne=iq
c----create 'A' boundary----
        iq=0
        xx=(1-nxc)*dx
        do i=1,ny
        iq=iq+1
        num(i,1)=iq
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo

        yy=(ny-nyc)*dy
        do i=2,nx-1
        iq=iq+1
        num(ny,i)=iq
        xx=(i-nxc)*dx
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo

        xx=(nx-nxc)*dx
        do i=ny,1,-1
        iq=iq+1
        num(i,nx)=iq
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo
        na=iq
c----create 'S' boundary----
        xx=(2-nxc)*dx
        do i=1,ny-1
        iq=iq+1
        num(i,2)=iq
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo

        yy=(ny-1-nyc)*dy
        do i=3,nx-2
        iq=iq+1
        num(ny-1,i)=iq
        xx=(i-nxc)*dx
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo

        xx=(nx-1-nxc)*dx
        do i=ny-1,1,-1
        iq=iq+1
        num(i,nx-1)=iq
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo
        ns=iq-na
c----create 'I' nodes----
        do j=3,nx-2
        do i=1,ny-2
        iq=iq+1
        num(i,j)=iq
        xx=(j-nxc)*dx
        yy=(i-nyc)*dy
        x(iq)=xx
        y(iq)=yy
        write (3,'(i3,2f10.5)') iq,xx,yy
        enddo
        enddo
        ni=iq-ns-na
        maxnum=iq

        do i=1,ny+1
        write (1,1) (num(i,j),j=0,nx+1)
        write (*,1) (num(i,j),j=0,nx+1)
1       format(20i4)
        enddo
c----generate mesh data----
        n=na+ns+ni
        write (*,'(2i5,4e10.3)') nx,ny,xd,yd,dx,dy
        write (2,'(2i5,4e10.3)') nx,ny,xd,yd,dx,dy
        write (*,'(5i10)') ne,na,ns,ni,n
        write (2,'(5i10)') ne,na,ns,ni,n
        do i=1,ny
        do j=1,nx
        write (*,1) num(i,j),num(i,j+1),num(i,j-1),num(i+1,j),num(i-1,j)
        write (2,1) num(i,j),num(i,j+1),num(i,j-1),num(i+1,j),num(i-1,j)
        enddo
        enddo
c----generate artificial boundary data----
c------left boundary----
        j=0
        do i=1,ny
        write (*,1) num(i,j),num(i,j+1)
        write (3,1) num(i,j),num(i,j+1)
        enddo
c------bottom boundary----
        i=ny+1
        do j=1,nx
        write (*,1) num(i,j),num(i-1,j)
        write (3,1) num(i,j),num(i-1,j)
        enddo
c------right boundary----
        j=nx+1
        do i=ny,1,-1
        write (*,1) num(i,j),num(i,j-1)
        write (3,1) num(i,j),num(i,j-1)
        enddo

        close(3)
        write (*,*) 'ne=',ne,nne

        open(3,file='coord.dat',status='old')
        do i=1,ne
        read (3,'(i3,2f10.5)') iq,xp(i),yp(i)
        enddo
        do i=1,ne
        read (3,1) ie,ia
        if((-ie).ne.i)then
          write (*,*) 'Index out of order.'
          stop
        endif
        write (2,'(i3,2f10.5,i3)') i,xp(i),yp(i),ia
        enddo
        close(3,status='delete')

        end