#! usr/bin/perl -wlnaF';'
use strict;

{
  my $outfile = "outfile.txt";
  my @result;

  # Assign fields to variables
  my $var1 = $F[0];     
  my $var2 = $F[1];     
  my $var3 = $F[2];     

  # Push fields into an array
  push @result, ( "$var1 $var2 $var3" );  

  # This debug print shows all 3 infile lines were processed
  print "Processed infile line no.: $.";

  END { 
    
    # This debug print shows only 1 element in array
    print "Array contains: " . @result . " element(s).";

    # pass array by reference and filename by value
    writeToFile( \@result, $outfile );
  }
}

sub writeToFile {
  # Takes a reference to an array and a filename as input
  # Writes the contents of the array to the file
  my $array_ref = $_[0];
  my $filename = $_[1];
  open OUTFILE, "> $filename"
    or die;
  foreach ( @{ $array_ref } ) {
    print OUTFILE;
  }
  close OUTFILE;
}