题解 | #树查找#结点忘记加入队列了，debug了好久

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <stack>
#include <map>
#include <queue>
#include <cmath>
using namespace std;

struct TreeNode {
    TreeNode* leftChild;
    TreeNode* rightChild;
    int data;
};

queue<TreeNode*> que;

int main() {
    int n;
    while (scanf("%d", &n) != EOF) {
        TreeNode* root = new TreeNode; //创造一个根结点

        root->leftChild = NULL;
        root->rightChild = NULL;
        scanf("%d", &root->data); //输入根结点的值
        que.push(root); //把根结点放入队列

        int curNodeNum = 1;
        while (curNodeNum < n) { //当前结点数量 < 要求的结点数量

            TreeNode* t = new TreeNode; //创建一个新的结点
            t->leftChild = NULL;
            t->rightChild = NULL;
            scanf("%d", &t->data); //输入该结点的值

            TreeNode* cur = que.front(); //当前队头结点
            que.pop();
            cur->leftChild = t; //把 t 放到 当前队头结点 的 左孩子
            que.push(t); //放入队列中
		  
            if (++curNodeNum >= n) { //如果加入这个结点以后就没了，就退出循环
                break;
            }

            TreeNode* t1 = new TreeNode; //再进行一次以上操作
            t1->leftChild = NULL;
            t1->rightChild = NULL;
            scanf("%d", &t1->data);

            cur->rightChild = t1; //放在右子树
            que.push(t1);
            if (++curNodeNum >= n) {
                break;
            }
        }

        int d;
        scanf("%d", &d);
        int total = 0;
        int two = 1;
        //计算一下在d这个深度有没有结点
        for (int j = 1; j < d; j++) {
            total += two;
            two *= 2;
        }
        if (n <= total) {
            printf("EMPTY\n");
            continue;
        }

        int curdeep = 1;
        while (!que.empty()) {
            que.pop();
        }
        que.push(root);
        while (curdeep != d) {
            int size = que.size();
            for (int i = 0; i < size; i++) {
                TreeNode* curnode = que.front();
                que.pop();
                if (curnode->leftChild != NULL) {
                    que.push(curnode->leftChild);
                }
                if (curnode->rightChild != NULL) {
                    que.push(curnode->rightChild);
                }
            }
            curdeep++;
        }
        //curdeep == d
        int size = que.size();
        for (int i = 0; i < size; i++) {
            TreeNode* curnode = que.front();
            que.pop();
            printf("%d ", curnode->data);
        }
        printf("\n");
    }
}