二叉树层序遍历生成实现

困惑点解答：

1.TNode_t 这里的_t代表typedef

//  main.cpp
//  二叉树层序遍历生成
//
//  Created by 郭宸羽 on 7/10/2022.
//

#include <stdlib.h>
#include <stdio.h>
#define Nodedata_type char

typedef struct TNode
{
    struct TNode * lchild;
    Nodedata_type data;
    struct TNode * rchild;
}TNode_t,*TNode_t_p;

typedef struct QNode
{
    TNode_t* TN_adr;
    struct QNode* next;
}QNode_t;

void Display(TNode_t_p& root)
{
    if(root == NULL)
        return;
    else
    {
        printf("%c ",root->data);
        Display(root->lchild);
        Display(root->rchild);
    }
}

int main()
{
    TNode* t_root_p = NULL,* t_tem_p = NULL;
    Nodedata_type TNode_data;
    QNode_t* q_head_p = NULL,*q_tail_p = NULL,*q_tem_p = NULL, *q_cur_p =NULL;//❓ ✓
    
    while (scanf("%c",TNode_data) != EOF)
    {
        if(TNode_data == '\n')
           break;
        
    //创建两个新结点——树的结点 & 队列的结点
        t_tem_p = (TNode_t*)calloc(1, sizeof(TNode_t));
        t_tem_p->data = TNode_data;
        
        q_tem_p = (QNode_t*)calloc(1, sizeof(QNode_t));
        q_tem_p->TN_adr = t_tem_p;
    //初始化树或者结点入队
        if(t_root_p == NULL)
        {
            t_root_p = t_tem_p;
            q_tail_p = q_cur_p = q_head_p = q_tem_p;
            continue;
        }
        else
        {
            q_tail_p->next = q_tem_p;
            q_tail_p = q_tem_p;
        }
     //将子结点连接子树的根
        if(q_cur_p->TN_adr->lchild == NULL)
        {
            q_cur_p->TN_adr->lchild = t_tem_p;
        }
        else if(q_cur_p->TN_adr->rchild == NULL)
        {
            q_cur_p->TN_adr->rchild = t_tem_p;
            q_cur_p = q_cur_p->next;
        }
    }
    Display(t_root_p);
}