这个程序怎么能让坐标标号连续  

  program ji
        PARAMETER (NPP=2100000,MEE=2100000)
real x(1000),y(1000)
integer   linenum(10),i,n
      open(1,file='line.txt',status='old')
open(2,file='g4.dat')  
         read(1,*)  n    !  
  read(1,*) lnum
      do 10 i=1,lnum
  
      read(1,*)linenum(i),x(i),y(i)  
   10 continue
       call disline (n,x(1),y(1),x(2),y(2))
       call disline (n,x(2),y(2),x(3),y(3))
       write (*,*)
  stop
  end
         subroutine disline(n,x0,y0,xn,yn)
real x(100),y(100)
        long=sqrt((x0-xn)*(x0-xn)+(y0-yn)*(y0-yn))!线段长度
        num=int(long/n)                       !节点数
        unitlo=long/num                           !等分线段
        dx=unitlo*(xn-x0)/long
        dy=unitlo*(yn-y0)/long
l=0
do 10 j=1,num+1
        l=l+1
        x(l)=x0+dx*(j-1)
y(l)=y0+dy*(j-1)
10 continue
        nod=l
        do 81 i=1,nod
write(2,109) i,x(i),y(i)
81 continue
109   format(i8,2E15.6)
end