二叉树的建议与遍历   出错了 （遍历出错了）
直接上代码吧
#include "malloc.h"
#include "stdio.h"

typedef struct trees
{
    char data;
    struct trees *lchild,*rchild;
}treelist,*treelink;

void maketree(treelink &root);
void display(treelink root);

int main(int argc, char* argv[])
{
    treelist *root;
    root = (treelink)malloc( sizeof(treelist));
    maketree(root);
    display(root);
    return 0;
}

void maketree(treelink &root)
{

    char ch;
    scanf("%c",&ch);
    if (ch == '#')
    {
        root = NULL;
    }
    else
    {
        root = (treelink)malloc(sizeof(treelist));
        root->data = ch;
        maketree(root->lchild);
        maketree(root->rchild);
    }
}


void display(treelink root)
{
    while (root != NULL)
    {
        printf("%c  ",root->data);
        display(root->lchild);
        display(root->rchild);
    }
}

#include "malloc.h"
#include "stdio.h"

typedef struct trees
{
    char data;
    struct trees *lchild,*rchild;
}treelist,*treelink;

void maketree(treelink &root);
void display(treelink root);

int main(int argc, char* argv[])
{
    treelist *root;
    root = (treelink)malloc( sizeof(treelist));
    maketree(root);
    display(root);
    return 0;
}

void maketree(treelink &root)
{

    char ch;
    scanf("%c",&ch);
    if (ch == '#')
    {
        root = NULL;
    }
    else
    {
        root = (treelink)malloc(sizeof(treelist));
        root->data = ch;
        maketree(root->lchild);
        maketree(root->rchild);
    }
}


void display(treelink root)
{
    if (root != NULL)   //不是while   自己的代码看了好半天才知道哪里错了  一开始还以为是建树错了，没想到是遍历错了！！！
    {
        printf("%c  ",root->data);
        display(root->lchild);
        display(root->rchild);
    }
} 

算了   我自己查出来了 ， 坑爹的错误

你这个先序遍历 就是递归调用而不是循环~~ 所以使用判断条件而不是循环语句！~ 不然又是循环又是递归~就很糟糕啦~

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