irtm boolean and

boolean_and_query.py

paris = [1, 2, 3, 4, 5, 7, 8, 9, 11, 12, 13, 14, 15]
france = [2, 6, 10, 12, 14]


def query(posting1, posting2):
    result = []
    it1 = iter(posting1)
    it2 = iter(posting2)

    el1 = next(it1)
    el2 = next(it2)

    s = max(len(posting1), len(posting2))

    for _ in range(s):
        try:
            if el1 == el2:
                result.append(el1)
                el1 = next(it1)
                el2 = next(it2)
            if el1 < el2:
                # go forward in 1
                el1 = next(it1)
            if el1 > el2:
                # go forward in 2
                el2 = next(it2)
        except StopIteration:
            break

    return result


r = query(paris, france)
print(r)