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There is a newer version: 10.3.1

package shz.core.queue.p;

import java.util.Comparator;

public final class ConcurrentMinPQueue extends ConcurrentRBBSTPQueue {
    private ConcurrentMinPQueue(Comparator comparator) {
        super(comparator);
    }

    public static  ConcurrentMinPQueue of(Comparator comparator) {
        return new ConcurrentMinPQueue<>(comparator);
    }

    @Override
    public E peek() {
        readLock.lock();
        try {
            if (root == null) return null;
            Node h = root;
            while (h.left != null) h = h.left;
            return h.e;
        } finally {
            readLock.unlock();
        }
    }

    @Override
    protected Node delTop(Node h) {
        if (h.left == null) return h.right;
        if (!isRed(h.left) && !isRed(h.left.left)) h = moveRedLeft(h);
        h.left = delTop(h.left);
        return balance(h);
    }
}