def cumsum(a, b, c=None, d=None, e=None):
    if e is not None:
        s1 = a + b
        s2 = s1 + c
        s3 = s2 + d
        return a, s1, s2, s3, s3 + e
    elif d is not None:
        s1 = a + b
        s2 = s1 + c
        return a, s1, s2, s2 + d
    elif c is not None:
        s = a + b
        return a, s, s + c
    else:
        return a, a + b