#!/usr/local/bin/perl
my %w; my $fn = shift; open my $fh, '<', $fn;
while(<$fh>) { chomp; $w{lc($_)}++  foreach(split /\s+/); }
print $w{$_},"\t",$_,"\n"
  foreach(sort { $w{$b} <=> $w{$a} or $a cmp $b } keys %w);