counter = Hash.new()
(97..122).each{|ord| counter[ord] = 0 }

characters = gets.chomp.split("")

characters.each {|c|
  ord = c.ord
  ord = ord + 32 if 65 <= ord && ord <= 90
  counter[ord] += 1 if counter.has_key?(ord)
}

puts counter.keys.map {|key| "#{key.chr} : #{counter[key]}"}.join("\n")