package tree.binarytree;
import java.util.Stack;
/**
* 2叉树的中序遍历：递归与非递归实现
*
* @author wl
*
*/
public class BiTreeInOrder {
// 中序遍历的递归实现
public static void biTreeInOrderByRecursion(BiTreeNode root) {
if (root == null) {
return;
}
biTreeInOrderByRecursion(root.leftNode);
System.out.println(root.data);
biTreeInOrderByRecursion(root.rightNode);
}
// 中序遍历的非递归实现
public static void biTreeInOrder(BiTreeNode root) {
Stack<BiTreeNode> stack = new Stack<BiTreeNode>();// 栈，用于寄存2叉树的结点
BiTreeNode current = root;// 当前结点
while (current != null || !stack.empty()) {
while (current != null) {
stack.push(current);
current = current.leftNode;
}
if (!stack.empty()) {
current = stack.pop();
System.out.println(current.data);
current = current.rightNode;
}
}
}
}