#include <stdio.h>
#include <stdlib.h>
typedef struct binarytree
{
    char data;
    struct binarytree *lchild;
    struct binarytree *rchild;
}node;
typedef node* Btree;
void create(Btree *t)
{
    char ch;
    if((ch=getchar())=='#')
        *t = NULL;
    else
    {
        *t = (node *)malloc(sizeof(node));
        (*t)->data = ch;
        (*t)->lchild = (*t)->rchild = NULL;
        create(&(*t)->lchild);
        create(&(*t)->rchild);
    }
}

void preorder(Btree t)
{
    if(t!=NULL)
    {
        printf("%c\n",t->data);
        preorder(t->lchild);
        preorder(t->rchild);
    }
}

void inorder(Btree t)
{
    if(t!=NULL)
    {
        inorder(t->lchild);
        printf("%c",t->data);
        inorder(t->rchild);
    }
}

void postorder(Btree t)
{
    if(t!=NULL)
    {
        postorder(t->lchild);
        postorder(t->rchild);
        printf("%c",t->data);
    }
}

int main(void)
{
    Btree p=NULL;
    create(&p);
    printf("Preoder traverse:\n");
    preorder(p);
    printf("\n");
    printf("Inorder traverse:\n");
    inorder(p);
    printf("\n");
    printf("Postorder traverse:\n");
    postorder(p);
    printf("\n");
    return 0;

}
为什么在输入#时没办法结束输入呢？

谢谢……，能在我的基础帮我改改这个程序吗？达到创建和遍历二叉树的目的。^-^

这个关系不大吧 我不是太明白