CShap 二叉树的lowest common ancestor 源代码

以下是C#中二叉树的lowest common ancestor的源代码：

using System;

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

    public Node(int value) {
        this.value = value;
        this.left = null;
        this.right = null;
    }
}

public class BinaryTree {
    public Node root;

    public BinaryTree() {
        this.root = null;
    }

    public Node LowestCommonAncestor(Node node, int value1, int value2) {
        if (node == null) {
            return null;
        }

        if (node.value == value1 || node.value == value2) {
            return node;
        }

        Node left = LowestCommonAncestor(node.left, value1, value2);
        Node right = LowestCommonAncestor(node.right, value1, value2);

        if (left != null && right != null) {
            return node;
        }

        return (left != null) ? left : right;
    }
}

public class Program {
    public static void Main() {
        BinaryTree tree = new BinaryTree();
        tree.root = new Node(1);
        tree.root.left = new Node(2);
        tree.root.right = new Node(3);
        tree.root.left.left = new Node(4);
        tree.root.left.right = new Node(5);
        tree.root.right.left = new Node(6);
        tree.root.right.right = new Node(7);

        Node lca = tree.LowestCommonAncestor(tree.root, 4, 5);
        Console.WriteLine("Lowest Common Ancestor of 4 and 5: " + lca.value);

        lca = tree.LowestCommonAncestor(tree.root, 4, 6);
        Console.WriteLine("Lowest Common Ancestor of 4 and 6: " + lca.value);

        lca = tree.LowestCommonAncestor(tree.root, 3, 4);
        Console.WriteLine("Lowest Common Ancestor of 3 and 4: " + lca.value);

        lca = tree.LowestCommonAncestor(tree.root, 2, 4);
        Console.WriteLine("Lowest Common Ancestor of 2 and 4: " + lca.value);
    }
}

在上面的代码中，我们定义了一个Node类和一个BinaryTree类。我们使用BinaryTree类来创建二叉树，并实现了一个LowestCommonAncestor方法来计算二叉树中给定两个节点的最近公共祖先。

在LowestCommonAncestor方法中，我们首先检查给定节点是否为null或与给定值之一匹配。如果是，则返回该节点。否则，我们递归地在左子树和右子树上调用LowestCommonAncestor方法，并检查它们的返回值。如果左子树和右子树的返回值都不为null，则当前节点是它们的最近公共祖先。否则，我们返回非null的那个子树的返回值。

在Main方法中，我们创建了一个二叉树，并测试了LowestCommonAncestor方法的几个不同输入。