#!/usr/bin/perl

@masses = (938.3, 939.6, 0.511);
@noms = ("proton", "neutron", "electron");
@indices = (0, 1, 2);
@indicestries = sort {$masses[$a] <=> $masses[$b]} (@indices);
foreach $tmp (@indicestries)
  {
    print ($noms[$tmp]." (".$masses[$tmp]." MeV)\n");
  }
