Question: lines of numbers separated with empty lines

Hi there,

I have the following problem:

I have lines with numbers; every several lines, the numbers are
separated with 2 empty lines. How can I count the # of lines
with numbers between 2 separations?

For example

1 2
2 3             4 lines here
3 4
4 5


1 2              2 lines here
5 6


2 3
3 4              3 lines here
4 5

Thank you!

/PS

The following program counts the number of non-blank lines between
blank lines. You could modify it to check that non-blank lines contain
two integers. Google Groups seems to mess up the indentation.

program xread
implicit none
integer                      :: ierr,nnum
integer, parameter           :: in_unit=20
character (len=100)          :: text
character (len=*), parameter :: in_file="read_test.dat"
open (unit=in_unit,file=in_file,action="read",status="old")
nnum = 0
do
read (in_unit,"(a)",iostat=ierr) text
if (ierr /= 0) then
print*,nnum
exit
end if
if (text == "") then
if (nnum > 0) print*,nnum
nnum = 0
else
nnum = nnum + 1
end if
end do
end program xread

output:
4
2
3

Thanks - it works fine!