leetcode 每日一题 1302. 层数最深叶子节点的和

leetcode 每日一题 1302. 层数最深叶子节点的和

//给你一棵二叉树的根节点 root ，请你返回 层数最深的叶子节点的和 。 
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// 示例 1： 
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//输入：root = [1,2,3,4,5,null,6,7,null,null,null,null,8]
//输出：15
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// 示例 2： 
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//输入：root = [6,7,8,2,7,1,3,9,null,1,4,null,null,null,5]
//输出：19
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// 提示： 
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// 树中节点数目在范围 [1, 10⁴] 之间。 
// 1 <= Node.val <= 100 
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//
// Related Topics 树 深度优先搜索 广度优先搜索 二叉树 👍 105 👎 0


//leetcode submit region begin(Prohibit modification and deletion)

import java.util.Deque;
import java.util.LinkedList;
import java.util.Stack;

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    private int num = 0;
    private int i = 0;
    private Deque<A> deque = new LinkedList();
    public int deepestLeavesSum(TreeNode root) {
        deque.add(new A(0,root));
        bfs();
        return num;
    }

    private void bfs() {
        A a = deque.pollFirst();
        if(a==null){
            return;
        }
        TreeNode root = a.getTreeNode();
        int i = a.getI();
        if(this.i == i){
            num += root.val;
        }else{
            num = root.val;
            this.i = i;
        }
        if(root.left != null){
            deque.add(new A(i+1,root.left));
        }
        if(root.right != null){
            deque.add(new A(i+1,root.right));
        }
        bfs();
    }

    class A{
        private int i;
        private TreeNode treeNode;

        public A(int i, TreeNode treeNode) {
            this.i = i;
            this.treeNode = treeNode;
        }

        public int getI() {
            return i;
        }

        public void setI(int i) {
            this.i = i;
        }

        public TreeNode getTreeNode() {
            return treeNode;
        }

        public void setTreeNode(TreeNode treeNode) {
            this.treeNode = treeNode;
        }
    }
}
//leetcode submit region end(Prohibit modification and deletion)