problems = input().strip().split(";")
expanded = []
for problem in problems:
    if "-" in problem:
        start = int(problem[: problem.index("-")])
        stop = int(problem[problem.index("-") + 1 :])
        for i in range(start, stop + 1):
            expanded.append(i)
    else:
        expanded.append(int(problem))
expanded = set(expanded)
print(len(expanded))