alpha = 'abcdefghijklmnopqrstuvwxyz'

text = ''



while True:

    try:

        text += input().lower()

    except:

        break

        

for key in alpha:

        print(('{} : {}'.format(key, text.count(key))))

alpha = 'abcdefghijklmnopqrstuvwxyz'

text = ''



while True:

    try:

        text += input().lower()

    except:

        break

 

[print('{} : {}'.format(key, text.count(key))) for key in alpha]

alpha = "abcdefghijklmnopqrstuvwxyz"
text = ""
while True:
    try:
        text += input().lower()
    except:
        break
for key in alpha:
    print(("{} : {}".format(key, text.count(key))))

alpha = "abcdefghijklmnopqrstuvwxyz"
text = ""
while True:
    try:
        text += input().lower()
    except:
        break
[print("{} : {}".format(key, text.count(key))) for key in alpha]

-for key in alpha: -    print(("{} : {}".format(key, text.count(key)))) +[print("{} : {}".format(key, text.count(key))) for key in alpha]