代码功能
这段Java代码定义了一个二叉树，并实现了两种遍历方法：深度优先搜索（DFS）和广度优先搜索（BFS）。通过DFS，代码从根节点开始，优先访问子节点，直至最深的节点；通过BFS，代码从根节点开始，逐层访问所有节点。最终，代码在控制台打印出两种遍历的节点值序列。
代码
import java.util.LinkedList;
import java.util.Queue;
import java.util.Stack;// 定义二叉树节点类
class TreeNode {int val;TreeNode left;TreeNode right;TreeNode(int x) {val = x;}
}public class BinaryTree {TreeNode root;// 构建二叉树public BinaryTree() {root = new TreeNode(1);root.left = new TreeNode(2);root.right = new TreeNode(3);root.left.left = new TreeNode(4);root.left.right = new TreeNode(5);root.right.left = new TreeNode(6);root.right.right = new TreeNode(7);}// 深度优先搜索（前序遍历）public void depthFirstSearch(TreeNode node) {if (node == null) {return;}System.out.print(node.val + " ");depthFirstSearch(node.left);depthFirstSearch(node.right);}// 广度优先搜索public void breadthFirstSearch(TreeNode node) {if (node == null) {return;}Queue<TreeNode> queue = new LinkedList<>();queue.add(node);while (!queue.isEmpty()) {TreeNode current = queue.poll();System.out.print(current.val + " ");if (current.left != null) {queue.add(current.left);}if (current.right != null) {queue.add(current.right);}}}public static void main(String[] args) {BinaryTree tree = new BinaryTree();System.out.println("深度优先搜索（前序遍历）输出：");tree.depthFirstSearch(tree.root);System.out.println();System.out.println("广度优先搜索输出：");tree.breadthFirstSearch(tree.root);}
}
)
