"""练习 2 进阶版：用生成器表达式和字典构造压缩统计步骤。"""
text = input()

letters = sum(ch.isascii() and ch.isalpha() for ch in text)
digits = sum(ch.isascii() and ch.isdigit() for ch in text)
spaces = text.count(" ")
char_counts = {ch: text.count(ch) for ch in dict.fromkeys(text)}

print("letters:", letters)
print("digits:", digits)
print("spaces:", spaces)
print("frequencies:")
for ch, count in char_counts.items():
    print(repr(ch), count)