#! perl5
#
# sglspc.pl Daniel Brockman 20030307 cvt dblspc to sglspc
#
# Usage: perl -- sglspc.pl < inputfile > outputfile

################################################
# The author grants permission to use for any  #
# purpose, including copying and modification, #
# provided the user acknowledges the author by #
# name.                                        #
# -- Daniel Brockman, author, 20031220         #
################################################
#
#

$prev=1; # 0=space, 1=nonspace, 2=prev part of continued line

while ($line=<>) {         # BIG LOOP
  $line=~s/[ \t]+\n/\n/g ; # remove trailing white space

  $linx=$line ;
  $linx=~s/[ \t\n]+//g ;

  if($linx=~m/^$/){      # it's a blank line
    if($prev==1) {  # prev line nonblank? go on to next.
      $prev=0;           # we hit insignificant blank
      next;              # get next line
    }
    print "$line";       # otherwise, print it
    $prev=1;             # its a significant blank
    next;                # and go on
  
  }else{                 # nonblank
        print "$line";   # print it
	$prev=1;
      
  }
        

} # end while BIG LOOP


  
#