count=Array.new(26)
for i in 0..25 do
  count[i]=0
end

while str=gets do
  i=0
  str.downcase!
  ("a".."z").each do |let|
    count[i]+=str.count(let)
    i+=1
  end
end

j=0
("a".."z").each do |let2|
  puts "#{let2} : #{count[j]}"
  j+=1
end