message = input("Enter message: ")

consecutive_counts: list[int] = []
counter = 0
prev_char = message[:1]

for char in message:
    if prev_char == char:
        counter += 1
        continue

    prev_char = char
    consecutive_counts.append(counter)
    counter = 1

# To account for the last segment
if message:
    consecutive_counts.append(counter)

for count in consecutive_counts:
    print(chr(ord('A') + count - 1), end='')