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struct Mo { int width; vector<int> left, right, order; vector<bool> v; Mo(int N, int Q) : width((int)sqrt(N)), order(Q), v(N) {
    iota(begin(order), end(order), 0);
  }
  void add(int l, int r) {
    left.emplace_back(l);
    right.emplace_back(r);
  }
  void run(const auto &add, const auto &del, const auto &rem) {
    assert(left.size() == order.size());
    sort(begin(order), end(order), [&](int a, int b) {
      int ablock = left[a] / width, bblock = left[b] / width;
      if (ablock != bblock)
        return ablock < bblock;
      if (ablock & 1)
        return right[a] < right[b];
      return right[a] > right[b];
    });
    int nl = 0, nr = 0;
    auto push = [&](int idx) {
      v[idx].flip();
      if (v[idx])
        add(idx);
      else
        del(idx);
    };
    for (auto idx : order) {
      while (nl > left[idx])
        push(--nl);
      while (nr < right[idx])
        push(nr++);
      while (nl < left[idx])
        push(nl++);
      while (nr > right[idx])
        push(--nr);
      rem(idx);
    }
  }
};