#!/usr/bin/env ruby1.9.1
STDIN.set_encoding 'utf-8'
shard_count_key = "__SHARD_COUNT__"
w = {}
c = {}
w.default = 0
c.default = 0
while line = STDIN.gets
key, val = line.split /\t/
w[key] += val.to_f
c[key] += 1.0
end
shard_count = w["__SHARD_COUNT__"]
w.each_key { |k|
if k == shard_count_key then next end
puts "#{k}\t#{w[k]/shard_count}"
}