Java数据结构课程设计 二叉树查找

题目：在二叉树中查找值为X的结点，试设计打印值为X的结点的所有祖先的算法，假设值为X的结点不多于1个。

import java.util.*;

public class BinTree {
	private List<Integer> binTree;

	public static void main(String[] args) {
		Scanner reader = new Scanner(System.in);
		int node;
		System.out.println("Build binary tree.");
		System.out.println("Enter number of tree node: ");
		int n = reader.nextInt();
		BinTree bt = new BinTree(n);
		System.out.println("Enter the " + n + " tree nodes");
		for (int i = 0; i < n; i++) {
			node = reader.nextInt();
			bt.addNode(node);
		}
		System.out.println("Enter the vaule X to find:");
		int target = reader.nextInt();
		if (bt.find(target)) {
			bt.printParentsOf(target);
		}
		else
			System.out.println("Can't find " + target);
	}

	public boolean find(int t) {
		return binTree.contains(t);
	}

	public void printParentsOf(int target) {
		int index = binTree.indexOf(target);
		if (index != 1) 
			printParentsOf(binTree.get(index/2));
		System.out.println(binTree.get(index));
	}

	public BinTree(int n) {
		binTree = new ArrayList<Integer>(n);
		binTree.add(0, -1); // 占位
	}

	public void addNode(int node) {
		binTree.add(node);
	}
}