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There is a newer version: 10.3.1
package shz.core.st.tst;

import shz.core.queue.a.SArrayQueue;
import shz.core.stack.l.LLinkedStack;

import java.util.Collections;
import java.util.function.Function;
import java.util.function.Predicate;

/**
 * 值为short类型的TST
 * 
 * 8+48*n(n为元素个数)
 * 

 * B=24+48*n
 */
public class ConcurrentSTST extends ConcurrentTST {
    /**
     * 2+27+对齐填充=32
     * 
     * B=48
     */
    protected static final class Node extends ConcurrentTST.Node {
        public short val;

        public Node(char c) {
            super(c);
        }
    }

    protected ConcurrentSTST() {
    }

    public static ConcurrentSTST of() {
        return new ConcurrentSTST();
    }

    public final void put(char[] a, short val) {
        acceptWrite(() -> root = put(root, a, val, 0));
    }

    protected final Node put(Node x, char[] a, short val, int d) {
        if (x == null) x = new Node(a[d]);
        if (a[d] < x.c) x.left = put(x.left, a, val, d);
        else if (a[d] > x.c) x.right = put(x.right, a, val, d);
        else if (d < a.length - 1) x.mid = put(x.mid, a, val, d + 1);
        else {
            x.val = val;
            x.leaf = true;
        }
        return x;
    }

    public final Short get(char[] a) {
        return applyRead(() -> {
            Node x = get(root, a, 0);
            return x == null || !x.leaf ? null : x.val;
        });
    }

    public final Iterable getAll() {
        return applyRead(() -> get(root, false));
    }

    protected final Iterable get(Node x, boolean prefix) {
        if (x == null) return Collections.emptyList();
        SArrayQueue queue = SArrayQueue.of();
        LLinkedStack stack = LLinkedStack.of();
        if (x.mid != null) stack.push(x.mid);
        if (!prefix) {
            if (x.left != null) stack.push(x.left);
            if (x.right != null) stack.push(x.right);
        }
        while (stack.size() > 0) {
            Node pop = stack.pop();
            if (pop.leaf) queue.offer(pop.val);
            push(stack, pop);
        }
        return queue.isEmpty() ? Collections.emptyList() : queue;
    }

    private void push(LLinkedStack stack, Node x) {
        if (x.left != null) stack.push(x.left);
        if (x.mid != null) stack.push(x.mid);
        if (x.right != null) stack.push(x.right);
    }

    public final Iterable getByPrefix(char[] prefix) {
        return applyRead(() -> get(get(root, prefix, 0), true));
    }

    public final Iterable getChars(Predicate predicate, int limit) {
        return applyRead(() -> getChars0(x -> predicate == null || predicate.test(x.val), limit));
    }

    public final Short computeIfAbsent(char[] a, Function func) {
        Short oldVal = get(a);
        if (oldVal != null) return oldVal;
        return applyWrite(() -> {
            Node x = get(root, a, 0);
            if (x != null && x.leaf) return x.val;
            Short val = func.apply(a);
            root = put(root, a, val, 0);
            return val;
        });
    }
}