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import UIKit

class CollectionViewCell: UICollectionViewCell {

    @IBOutlet weak var label: UILabel!
}

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var tableView: UITableView!
    fileprivate var tableViewCellCoordinator: [IndexPath: Int] = [:]

    override func viewDidLoad() {
        super.viewDidLoad()
        tableView.dataSource = self
        tableView.delegate = self
        tableView.tableFooterView = UIView()
    }
}

// UITableViewDataSource

extension ViewController: UITableViewDataSource {

    func numberOfSections(in tableView: UITableView) -> Int {
        return 5
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 10
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "CollectionViewTableViewCell") as! CollectionViewTableViewCell

        cell.collectionView.delegate = self
        cell.collectionView.dataSource = self

        let tag = 10000*(indexPath.section+1)+indexPath.row
        cell.collectionView.tag = tag
        tableViewCellCoordinator[indexPath] = tag

        return cell
    }

    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        return "section: \(section)"
    }

}

extension ViewController: UITableViewDelegate {
    func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
        let cell = cell as! CollectionViewTableViewCell
        cell.collectionView.reloadData()
        cell.collectionView.contentOffset = .zero
    }
}

// UICollectionViewDataSource

extension ViewController: UICollectionViewDataSource {

    func numberOfSections(in collectionView: UICollectionView) -> Int {
        return 1
    }

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 10
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "CollectionViewCell", for: indexPath) as! CollectionViewCell
        return cell
    }
}

// UICollectionViewDelegate

extension ViewController: UICollectionViewDelegate {

    func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
        let cell = cell as! CollectionViewCell
        cell.label.text = "\(tableViewCellCoordinator.key(forValue: collectionView.tag)!) \(indexPath)"
    }

    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        print("selected collectionViewCell with indexPath: \(indexPath) in tableViewCell with indexPath: \(tableViewCellCoordinator.key(forValue: collectionView.tag)!)")
    }

}

import UIKit

class CollectionViewTableViewCell: UITableViewCell {

    @IBOutlet weak var collectionView: UICollectionView!
    @IBOutlet weak var collectionViewFlowLayout: UICollectionViewFlowLayout!
}