Question

我在SOF上在线推荐一些资料后实施了LCA算法。输出结果将是一些字符，如下所示。有谁可以解释下面我的代码中出了什么问题？

package trees;

public class LowestCommonAncestorBinaryTree {

    static class Node {
        Node left;
        Node right;
        int value;

        public Node(int value) {
            left = null;
            right = null;
            this.value = value;
        }
    }
    // Source for below method : http://stackoverflow.com/questions/12056068/finding-least-common-ancestor-in-binary-tree
    public static Node findLca(Node node, int t1, int t2) {
        if(node == null) {
            return null;
        }
        if(node.value > t2 && node.value > t1) {
            // both targets are left
            return findLca(node.left, t1, t2);
        } else if (node.value < t2 && node.value < t1) {
            // both targets are right
            return findLca(node.right, t1, t2);
        } else {
            // either we are diverging or both targets are equal
            // in both cases so we've found the LCA
            // check for actual existence of targets here, if you like
            return node;
        }
    }


    public static void main(String[] args) {

        /**
         * Create a sample Binary Tree. A Binary tree does not have to maintain
         * left <root < right relationship.
         */
        Node root = new Node(1);
        root.left = new Node(2);
        root.right = new Node(4);
        root.left.left = new Node(6);
        root.left.right = new Node(5);

        root.right.left = new Node(9);
        root.right.right = new Node(11);
        root.right.right.left = new Node(7);
        root.right.right.right = new Node(3);


        System.out.println("Lowest Common Ancestor of Node 3 and 9 is: "
                + findLca(root, 3,9));


    }

}

以下是我得到的输出：节点3和9的最低公共祖先是：trees.LowestCommonAncestorBinaryTree$Node@6d06d69c

Answer 1

您刚刚没有为您的班级toString()定义Node。字符串"trees.LowestCommonAncestorBinaryTree$Node@6d06d69c"由默认toString()生成。

您可以将行打印结果更改为：

System.out.println("Lowest Common Ancestor of Node 3 and 9 is: "
            + findLca(root, 3,9).value);

输出返回字符

1 个答案: