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#!/usr/bin/perl

#Open the input and output files

open (INPUT, $ARGV[0]);

if (-e "$ARGV[0].np") {
    die "Output file exists!";
} else {
    open (OUTPUT, ">$ARGV[0].np");
}

#Step through input file, one line at a time, and

while () {
	
#Check to see if the line is the beginning of a new NP, and:

    if (/^\(/) {

   #If so
      #The previous NP is finished, print it to the output file.

	print OUTPUT "$this_np\n";

      #See how long the label is.
     
	@line = split;
	$np_label = $line[0]; # $np_label is the label plus the leading (.
	$offset = length($np_label);

      #Get the first node after the label, and remember it as 
      #the first part of a string describing the immediate constituents.

	$first_daughter = $line[1];
	$first_daughter = substr($first_daughter,1);
	$this_np = $first_daughter;

   #Otherwise
      #See if there is a node label in the right place for
      #immediate constituents.

    } elsif (substr($_, $offset+1, 1) eq "(") {

      #If so
         #Get the label of the node

	@line = split;
	$this_daughter = $line[0];
        $this_daughter = substr($this_daughter,1);

         #Add it to your string of immediate constituents

	$this_np = $this_np." ".$this_daughter;
    } 

}

#Print the last NP found.

print OUTPUT "$this_np\n";

#Close input and output files.

close (INPUT);
close (OUTPUT);

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