package bintree;

public class BinTreeFullSyncEdited implements BinTree {

	private static class Node {
		final int value;
		int occ;
		Node left, right;

		private Node(int value, int initOcc) {
			this.value = value;
			occ = initOcc;
		}

		private synchronized int getOcc() {
			return occ;
		}

		private synchronized void incrementOcc() {
			occ++;
		}

		private synchronized Node goLeftOrNull(int value) {
			if (this.left == null) {
				this.left = new Node(value, 1);
				return null;
			}
			return this.left;
		}

		private synchronized Node goRightOrNull(int value) {
			if (this.right == null) {
				this.right = new Node(value, 1);
				return null;
			}
			return this.right;
		}
	}

	private final Node root = new Node(0, 0);

	public void insert(int value) {
		Node n = root;
		while (n != null) {
			int nval = n.value;
			if (value == nval) {
				n.incrementOcc();
				return;
			} 
			else if (value < nval) { 
				n = n.goLeftOrNull(value);
			} 
			else { // value > nval
				n = n.goRightOrNull(value);
			} 
		}
	}

	public int occurs(int value) {
		Node n = root;
		do {
			int nval = n.value;
			if (value == nval) {
				return n.getOcc();
			}
			n = (value < nval) ? n.left : n.right;
		} while (n != null);
		// value not found
		return 0;
	}
}