alphabet = {}
('a'..'z').each do |a|
	alphabet[a] = 0
end

while (str = gets) != STDIN.eof do
	('a'..'z').each do |a|
		alphabet[a] += str.downcase.count(a)
	end
end

('a'..'z').each do |a|
	puts "#{a} : #{alphabet[a]}" 
end