solve the following question in cpp which is given...

Below is a drop‑in implementation of scheduleRequests that runs in O(n log n) using a Fenwick tree (Binary Indexed Tree).
It builds the final queue by processing insertions from right to left: for each i, it places request[i] into the (index[i]+1)‑th empty slot.

cpp
vector<int> scheduleRequests(vector<int> index, vector<int> request) {
    int n = (int)index.size();
    vector<int> ans(n);

    // Fenwick Tree (1-indexed) to track empty slots.
    vector<int> bit(n + 1, 0);
    auto add = [&](int i, int delta) {
        for (; i <= n; i += i & -i) bit[i] += delta;
    };
    auto kth = [&](int k) {
        // Find smallest pos such that sum(bit[1..pos]) >= k
        int pos = 0;
        int step = 1;
        while ((step << 1) <= n) step <<= 1;  // highest power of two <= n
        for (int p = step; p; p >>= 1) {
            int next = pos + p;
            if (next <= n && bit[next] < k) {
                k -= bit[next];
                pos = next;
            }
        }
        return pos + 1; // 1-indexed position
    };

    // Initially, every position is empty (value 1).
    for (int i = 1; i <= n; ++i) add(i, 1);

    // Place requests from right to left.
    for (int i = n - 1; i >= 0; --i) {
        int k = index[i] + 1;        // k-th empty slot to fill
        int pos = kth(k);            // position in 1..n
        ans[pos - 1] = request[i];   // store value
        add(pos, -1);                // mark slot as filled
    }
    return ans;
}

Verified on the given examples

• index = [0,1,2,1,2], request = [0,1,2,3,4] → [0, 3, 4, 1, 2]
• Sample 0: index=[0,1,1], request=[0,1,2] → [0, 2, 1]
• Sample 1: index=[0,0], request=[0,1] → [1, 0]
• Sample 2: index=[0,1,0], request=[0,1,2] → [2, 0, 1]

This matches the step-by-step outcomes described in the problem statement.