#!/usr/bin/perl
use strict;
use warnings;

my $best = {1 =>[1,2]};
my $kept_best = {1 =>[1]};

my $width = 10;
my $precision = 5;
my $format = "\%${width}.${precision}f ";

printf "%-${width}s %-${width}s\n", "BEST", "SELECTED BEST";
foreach my $value (sort keys %$best){
    foreach my $bind_energy (@{$best->{$value}}){
        printf $format, $bind_energy;
        
        my $kept = shift @{$kept_best->{$value}};
        printf $format, $kept if defined $kept;
        
        print "\n";
    }
}