program specint
      implicit none
      character*80 fl,s,fn
      integer*4 i,j,k,n,nf,nl,np,iargc
      real*8 v
      real*8,allocatable:: a(:),b(:),ai(:),x(:),y(:)

      write(6,6000)
6000  format(/,' Integral of spectra in several ranges',/,/,
     1         '    Usage: specint <file.lst> n a1 b1 ... an bn',/)
      if(iargc().lt.4)stop
      call getarg(1,fl)
      call getarg(2,s)
      read(s,*)n
      allocate(a(n),b(n),ai(n))
      do 3 i=1,n
      call getarg(2*i+1,s)
      read(s,*)a(i)
      call getarg(2*i+2,s)
3     read(s,*)b(i)
c     how many lines in fl:
      nf=nl(fl)
      write(6,*)nf,' files'

c     how many points in the first:
      open(9,file=fl)
      read(9,80)fn
80    format(a80)
      close(9)
      np=nl(fn)
      write(6,*)np,' points'
      allocate(x(np),y(np))

      open(9,file=fl)
      open(8,file='t.prn')
      do 1 i=1,nf
      read(9,80)fn
      open(10,file=fn)
      do 2 j=1,np
2     read(10,*)x(j),y(j)
      close(10)
      ai=0.0d0
      do 5 j=2,np-1
      v=dabs((x(j+1)-x(j-1))/2.0d0)
      do 5 k=1,n
5     if(a(k).le.x(j).and.x(j).le.b(k))ai(k)=ai(k)+y(j)*v
      write(6,600)i
      write(8,600)i
600   format(i6,$)
      do 4 k=1,n
      write(6,601)ai(k)
4     write(8,601)ai(k)
601   format(E14.4,$)
      write(6,*)
1     write(8,*)
      close(9)
      close(8)

      end

      function nl(f)
      implicit none
      character*(*) f
      integer*4 nl,n
      open(9,file=f)
      n=0
1     read(9,*,end=99,err=99)
      n=n+1
      goto 1
99    close(9)
      nl=n
      return
      end