#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <conio.h>
//二叉树
typedef struct BiTreeNode
{
    char book_name[20];
    char writer[10];
    int year;
    struct BiTreeNode * lchild;
    struct BiTreeNode * rchild;
}Book;

Book * InitBiTree()
{
     Book * BookList;
     BookList = (Book *)malloc(sizeof(Book));
     strcpy(BookList->book_name,"");
     strcpy(BookList->writer,"");
     BookList->year=-1;
     BookList->lchild=0;
     BookList->rchild=0;
     return BookList;
}


void Insert(Book * BookList, Book * newBook)
{
    if (strcmp(BookList->book_name,newBook->book_name)>0)  //这里输入<就无显示了
    {
        if (BookList->lchild==0)
            BookList->lchild=newBook;
        else
            Insert(BookList->lchild, newBook);//递归调用
    }

    else
    {
        if (BookList->rchild==0)
           BookList->rchild=newBook;
        else
           Insert(BookList->rchild, newBook);//递归调用
    }
}


void InOrder(Book * BookList)
{
    if (BookList==0) return;
    if (BookList->year!=-1)
    {
        InOrder(BookList->lchild);

        printf("%s\t%s\t%d\n",BookList->book_name,
                BookList->writer, BookList->year);
    }
    InOrder(BookList->rchild);
}


int main()
{
    Book * BOOK=0;
    Book * newBook=0;

    BOOK=InitBiTree();

    newBook = (Book *)malloc(sizeof(Book));
    strcpy(newBook->book_name,"c#程序设计教程");
    strcpy(newBook->writer,"李春葆");
    newBook->year=2010;
    newBook->lchild=0;
    newBook->rchild=0;
    Insert(BOOK, newBook);
    printf("加入一本书以后：\n");
    InOrder(BOOK);
    printf("\n");

    newBook = (Book *)malloc(sizeof(Book));
    strcpy(newBook->book_name,"实用数据结构");
    strcpy(newBook->writer,"陈明");
    newBook->year=2009;
    newBook->lchild=0;
    newBook->rchild=0;
    Insert(BOOK, newBook);
    printf("加入一本书以后：\n");
    InOrder(BOOK);

    printf("\n");
    newBook = (Book *)malloc(sizeof(Book));
    strcpy(newBook->book_name,"应用数学");
    strcpy(newBook->writer,"吴静");
    newBook->year=2011;
    newBook->lchild=0;
    newBook->rchild=0;
    Insert(BOOK, newBook);
    printf("加入一本书以后：\n");
    InOrder(BOOK);
    printf("\n");

    newBook = (Book *)malloc(sizeof(Book));
    strcpy(newBook->book_name,"职业生涯规划");
    strcpy(newBook->writer,"谢彩英");
    newBook->year=2011;
    newBook->lchild=0;
    newBook->rchild=0;
    Insert(BOOK, newBook);
    printf("加入一本书以后：\n");
    printf("书名\t\t作者\t出版年份\n");
    InOrder(BOOK);
    getch();
}
求解

[ 本帖最后由 lxh30907 于 2011-5-15 10:51 编辑 ]

没人知道？

要问什么？

if (strcmp(BookList->book_name,newBook->book_name)>0)  
在这里把 > 改成 < 就无显示了
   

粗略看了一下，首先说你的根节点问题，根结点的数据为空，那么所有数据都肯定是大于根节点的，这样最后所有数据在一边，建议根节点赋第一本书的值，这样有利于比较
另外一个就是另外一个问题，就是这个遍历----void InOrder(Book * BookList)，遍历条件不合理，只能访问根节点的右子树，无法访问根节点的左子树

你的输出的问题主要是改了符号后全部在另外一个子树上，而遍历只遍历根结点的右子树，故无法输出

你自己再仔细看看吧，感觉程序设计不太合理


[ 本帖最后由 baobaoisme 于 2011-5-15 23:16 编辑 ]

strcmp就是按字典排序