#!/usr/bin/perl

# Calculate the session length distribution (number of hits)
# Author: Ian Hickman

use strict;

my $c=0;
my (%table, $key);

while( <STDIN> ){
  # remove newline
  chomp( $_ );

  # if in a session
  if( $_ ne "" ){
    $c++;
  } else {
    $table{$c}++;
    $c=0;
  }
}

foreach $key ( keys ( %table )){
  print"$key $table{$key}\n";
}