public class BinaryTree {

public TreeNode root;// 成员变量

protected BinaryTree() {

}

public BinaryTree(Integer[] nums) {

root = createNode(0, nums);

}

private TreeNode createNode(int n, Integer[] nums) {

if (n >= nums.length || nums[n] == null) {

return null;

}

TreeNode node = new TreeNode(nums[n].intValue());

node.left = createNode(2 * n + 1, nums);

node.right = createNode(2 * n + 2, nums);

return node;

}

public void print() {

printTree(root);

System.out.println();

}

public void printPre() {

PreOrder(root);

System.out.println();

;

}

public void printPost() {

PostOrder(root);

System.out.println();

}

static void printTree(TreeNode node) {// in-order Traversal

if (node == null)

return;

System.out.print(node.val + " ");

printTree(node.left);

printTree(node.right);

}

public void PreOrder(TreeNode node) {

if (node == null) {

return;

}

System.out.print(node.val + " ");

PreOrder(node.left);

PreOrder(node.right);

}

private static void PostOrder(TreeNode node) {

if (node == null) {

return;

}

PostOrder(node.left);

PostOrder(node.right);

System.out.print(node.val + " ");

}

}