Hard Range

struct hardRange {
    int n;
    map<int, set<int>> pos;
    vector<ordered_set> Tree;

    hardRange(int size) {
        n = size;
        Tree.resize(4 * n);
    }

    void add(int pos, int nxt, int v, int l, int r) {
        if (l > pos || pos > r) return;
        Tree[v].insert(nxt);
        if (l != r) {
            int mid = (l + r) / 2;
            add(pos, nxt, 2 * v, l, mid);
            add(pos, nxt, 2 * v + 1, mid + 1, r);
        }
    }

    void remove(int pos, int nxt, int v, int l, int r) {
        if (l > pos || pos > r) return;
        Tree[v].erase(Tree[v].find_by_order(Tree[v].order_of_key(nxt)));
        if (l != r) {
            int mid = (l + r) / 2;
            remove(pos, nxt, 2 * v, l, mid);
            remove(pos, nxt, 2 * v + 1, mid + 1, r);
        }
    }

    ll rangeQuery(int tl, int tr, int v, int l, int r, int R) {
        if (l > tr || r < tl) return 0;
        if (l >= tl && r <= tr) return Tree[v].size() - Tree[v].order_of_key(R + 1);
        int mid = (l + r) / 2;
        return rangeQuery(tl, tr, 2 * v, l, mid, R) + rangeQuery(tl, tr, 2 * v + 1, mid + 1, r, R);
    }

    ll query(int a, int b) {
        return rangeQuery(a, b, 1, 0, n - 1, b);
    }

    void rem(int idx, int val) {
        auto it = pos[val].find(idx);
        int nxt = n + val;
        int prev = -1;
        if (it != pos[val].begin()) {
            prev = *(--it);
            it++;
        }
        it++;
        if (it != pos[val].end()) nxt = *it;
        it--;
        remove(idx, nxt, 1, 0, n - 1);
        if (prev != -1) {
            remove(prev, idx, 1, 0, n - 1);
            add(prev, nxt, 1, 0, n - 1);
        }
        pos[val].erase(it);
    }

    void insert(int idx, int val) {
        pos[val].insert(idx);
        auto it = pos[val].find(idx);
        int prev = -1;
        int nxt = n + val;
        if (it != pos[val].begin()) {
            prev = *(--it);
            it++;
        }
        it++;
        if (it != pos[val].end()) nxt = *it;
        it--;
        if (prev != -1) {
            remove(prev, nxt, 1, 0, n - 1);
            add(prev, idx, 1, 0, n - 1);
        }
        add(idx, nxt, 1, 0, n - 1);
    }
};