package binarytree;import linkqueue.LinkQueue;public class BinaryTree {class Node{public Object data;public Node lchild;public Node rchild;public Node(Object data){this.data = data;this.lchild = null;this.rchild = null;}}//根节点private Node root = null;private Node node = null;/*** 创建树* * 以完全二叉树的格式来创建（子树不存在的用0填充），* 对完全二叉树中每一个节点从0开始进行编号，* 那么第i个节点的左孩子的编号为2*i+1，右孩子为2*i+2。* * */void createTree(String strtree){LinkQueue lQueue = new LinkQueue();lQueue.initQueue();/*** 完全二叉树中第i层的结点的个数最多为第1到i-1层上所有节点的个数和* 所以父节点的个数最多为N-1个，N表示节点个数* */for(int parentIndex =0; parentIndex<strtree.split(" ").length/2;parentIndex++){if(root == null){root= new Node(strtree.split(" ")[parentIndex]);//左孩子root.lchild = new Node(strtree.split(" ")[parentIndex*2+1]);lQueue.enQueue(root.lchild);//右孩子root.rchild = new Node(strtree.split(" ")[parentIndex*2+2]);lQueue.enQueue(root.rchild);}else{if(!lQueue.isEmpty() && parentIndex*2+1<strtree.split(" ").length)//队列不空{node = (Node) lQueue.deQueue();if(parentIndex*2+1<strtree.split(" ").length){//左孩子node.lchild = new Node(strtree.split(" ")[parentIndex*2+1]);lQueue.enQueue(node.lchild);}if(parentIndex*2+2<strtree.split(" ").length){//右孩子node.rchild = new Node(strtree.split(" ")[parentIndex*2+2]);lQueue.enQueue(node.rchild);}}else{return;}}}}/*** 先序遍历二叉树* */void preOrderTraverse(Node node){if(node == null){return;}visit(node);preOrderTraverse(node.lchild);preOrderTraverse(node.rchild);}/*** 中序遍历二叉树* */void inOrderTraverse(Node node){if(node == null){return;}inOrderTraverse(node.lchild);visit(node);inOrderTraverse(node.rchild);}/*** 后序遍历二叉树* */void postOrderTraverse(Node node){if(node == null){return;}postOrderTraverse(node.lchild);postOrderTraverse(node.rchild);visit(node);}/*** 打印二叉树* */public void print(){System.out.print("先序遍历：");preOrderTraverse(root);System.out.print("\n中序遍历：");inOrderTraverse(root);System.out.print("\n后序遍历：");postOrderTraverse(root);}/*** 访问节点* */private void visit(Node node){if(!node.data.equals("0")){System.out.print(node.data+" ");}}
}

package binarytree;public class BinaryTreeMain {public static void main(String[] args) {BinaryTree binaryTree = new BinaryTree();String strtree="- + / a * e f 0 0 b - 0 0 0 0 0 0 0 0 0 0 c d";//0表示没有值的位置binaryTree.createTree(strtree);binaryTree.print();}}