sentence = []
while
  sentence << gets.chomp
  break if gets == "\n"
end
str=sentence.join.delete(" ").downcase
alphabet=("a".."z").to_a
1.upto(alphabet.size) do |i|
  if str.count(alphabet[i-1])==0
    print alphabet[i-1]," : 0\n"
  else
    print alphabet[i-1]," : ",str.count(alphabet[i-1]),"\n"
  end
end