2.py

s = input()
arr = []
while s:
    arr += s.split()
    s = input()

res = {}
for word in arr:
    key = word[-1].upper()
    if key in res:
        if word.lower() not in res[key]:
            res[key].append(word.lower())
    else:
        res[key] = [word.lower()]

for key in res.keys():
    print(f"{key} - ", end="")
    print(*sorted(res[key]), sep=", ")