sum_of_2_numbers_while

start = int(input())
end = int(input())
magic_number = int(input())

is_found = False
count = 0

for i in range(start, end+1):
    if is_found:
        break
    for j in range(start, end+1):
        count += 1
        result = i + j
        if result == magic_number:
            is_found = True
            print(f"Combination N:{count} ({i} + {j} = {magic_number})")
            break
if not is_found:
    print(f"{count} combinations - neither equals {magic_number}")