def InitializeDictionary(Dict):
    for letter in "abcdefghijklmnopqrstuvwxyz":
        Dict[letter] = 0

def AddToCounts(s, D):
    for letter in s.lower():
        if letter in D.keys():
            D[letter] += 1

def PrintCounts(D):
    for letter in D.keys():
        print "%s: %d" % (letter, D[letter] )
        
def main():
    D = {}
    InitializeDictionary(D)

    done = False
    while not done:
        string = raw_input("Enter text or blank line to exit: ")
        if string == "":
            done = True
        else:
            AddToCounts(string, D)
    PrintCounts(D)

main()