Question

我有以下代码在每个级别打印二叉树。但是我不想要当前的输出，我需要额外的金字塔空间结构：

import java.util.LinkedList;
import java.util.Queue;

public class LevelOrder 
{
static class Node
{
    int data;
    Node left;
    Node right;

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

static void printLevelOrder(Node root)
{
    if(root == null)
        return;

    Queue<Node> q =new LinkedList<Node>();

    q.add(root);            
    while(true)
    {               
        int nodeCount = q.size();
        if(nodeCount == 0)
            break;

        while(nodeCount > 0)
        {    
            Node node = q.peek();
            System.out.print("("+node.data + ")");

            q.remove();

            if(node.left != null)
                q.add(node.left);
            if(node.right != null)
                q.add(node.right);

            if(nodeCount>1){
               System.out.print(", ");
            }
            nodeCount--;    
        }     
        System.out.println();
    }
}       
public static void main(String[] args) 
{           
    Node root = new Node(6);
    root.left = new Node(3);
    root.right = new Node(2);
    root.left.left = new Node(8);
    root.left.right = new Node(9);
    root.right.right = new Node(-2);
    root.right.left = new Node(3);
    printLevelOrder(root);    
   }

}

我的当前输出为AS FOLLOWS：

(6)
(3), (2)
(8), (9), (3), (-2)

但我需要这样的东西：

       (6)
    (3),  (2)
 (8), (9), (3), (-2)

如何以有效的方式打印上述输出所需的空格。请帮忙。

Answer 1

实际上你得到了正确的输出，但你没有得到正确格式的输出。要做到这一点，你必须将相应的输出显示为三角形。我必须用我的代码完成它。如果你得到任何问题，随时发表评论。我一定会帮助你。

试用此代码： -

import java.util.LinkedList;
import java.util.Queue; 
public class LevelOrder
 { 
 static class Node
 { int data; Node left; Node right;
Node(int data) 
{
this.data = data;
left = null;
right = null;
depth = 1;
}
}

static void printLevelOrder(Node root) 
{
if (root == null)
    return;

Queue < Node > q = new LinkedList < Node > ();

q.add(root);
while (true)
 {
    int nodeCount = q.size();
    if (nodeCount == 0)
        break;

    while (nodeCount > 0)
 {
        Node node = q.peek();
        System.out.print("(" + node.data + ")");

        q.remove();

        if (node.left != null)
            q.add(node.left);
        if (node.right != null)
            q.add(node.right);
        if (node.depth != null)
            System.out.print(" ");
        if (nodeCount > 1)
 {
            System.out.print(", ");
        }

        nodeCount--;
    }
    System.out.println();
}
}
public static void main(String[] args)
 {
Node root = new Node(6);
root.left = new Node(3);
root.right = new Node(2);
root.left.left = new Node(8);
root.left.right = new Node(9);
root.right.right = new Node(-2);
root.right.left = new Node(3);
printLevelOrder(root);
}
}

Answer 2

这是你正在寻找的，我介绍了一种方法，计算树的深度，并根据你打印节点的级别，我相应地介绍空格。

import java.util.LinkedList;
import java.util.Queue;

public class Main 
{
static class Node
{
    int data;
    Node left;
    Node right;

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

static int depthOfTree(Node root, int d) {
  if(root == null) {
    return d;
  }
  int left = d;
  int right = d;
  if(root.left != null) {
    left = depthOfTree(root.left, d+1);
  }
  if(root.right != null) {
    right = depthOfTree(root.right, d+1);
  }
  return Math.max(left, right);
}

static void printLevelOrder(Node root, int depth)
{
    if(root == null)
        return;

    Queue<Node> q =new LinkedList<Node>();

    q.add(root);            
    while(true)
    {               
        int nodeCount = q.size();
        if(nodeCount == 0)
            break;
        for(int i=0; i<depth; i++) {
          System.out.print("  ");
        }
        while(nodeCount > 0)
        {    
            Node node = q.peek();
            System.out.print("("+node.data + ")");

            q.remove();

            if(node.left != null)
                q.add(node.left);
            if(node.right != null)
                q.add(node.right);

            if(nodeCount>1){
               System.out.print(", ");
            }
            nodeCount--;    
        }
        depth--;
        System.out.println();
    }
}       
public static void main(String[] args) 
{           
    Node root = new Node(6);
    root.left = new Node(3);
    root.right = new Node(2);
    root.left.left = new Node(8);
    root.left.right = new Node(9);
    root.right.right = new Node(-2);
    root.right.left = new Node(3);
    int d = depthOfTree(root, 1);
    //System.out.println(d);
    printLevelOrder(root, d);    
   }

}

希望这有帮助！

在Java中打印具有适当空间的二叉树

2 个答案: