if (deltadist < 0) continue;

        if (deltadist < 0)
            continue;

            if (!dest.is_valid()) continue;

            if (!dest.is_valid())
                continue;

    for (std::vector<stair_info>::iterator i = stairs.begin(); 
            i != stairs.end(); ++i)

    for (int i = ((int) stairs.size()) - 1; i >= 0; --i)

            if (s[j] == i->position)

            if (s[j] == stairs[i].position)

            stairs.erase(i--);

            stairs.erase(stairs.begin() + i);

    stair_distances.reserve( stairs.size() * stairs.size() );

    const int nstairs = stairs.size();
    stair_distances.reserve( nstairs * nstairs );
    stair_distances.resize( nstairs * nstairs, 0 );

        for (int i = stair_count * stair_count - 1; i >= 0; --i)

        const int sz = stair_distances.size();
        for (int i = 0, n = stair_count * stair_count; i < n; ++i)

            if (i >= (int) stair_distances.size())

            if (i >= sz)