#!/usr/bin/perl

use strict;
use warnings;

my %Consumption;
my @headers;

foreach my $filename (@ARGV){
   Extract_info_From_File_Into_Consumption ($filename);
}
# Print output

print "Dist\t@headers\n";
for my $dist (sort {$a <=> $b} keys %Consumption){
    my $line = "$dist\t";
    $line .= "\t$_" for @{$Consumption{$dist}};
    print "$line\n";
}

#----------------
sub Extract_info_From_File_Into_Consumption {
   my $filename = shift;
   open my $f , "<", $filename or die "Could not open $filename : $!";
   my ($head1,$head2) = split /\s+/ ,<$f>,2 or die "No data in $filename";
   chomp $head2;
   my $index = scalar @headers;
   $headers[$index] = "$head2\_$filename";
   while (<$f>){
	  my ($dist, $consume) = m/(\d+\.?\d*)/g;
	  $Consumption{$dist}[$index] = $consume;  
   }
   close $f;
}