a strange problem :(

I study the data structure,
met a strange problem.
I used preorder method to create a binary tree;
code :

Code:

---

#include<stdio.h>
typedef struct node {
        int  data;
        struct node *left;
        struct node *right;}btree;

btree *Binarytree(btree *bt)
{
  int data;
  scanf("%d",&data);
  if(data==0)
    bt=NULL;
  else
  { bt=(btree *)malloc(sizeof(btree));
    bt->data=data;
    Binarytree(bt->left);
    Binarytree(bt->right);
  }
  return bt;
}

main()
{
  btree *bt;
  bt=(btree *)malloc(sizeof(btree));
  printf("\n\t\tThe Binary Tree:\n");
  printf("\nPlease input the data of binary tree(0 for NULL) :\n");
  Binarytree(bt);
}

---

Now I want to traverse the tree,and put out the result---
each node's data;
And the problem comes, when I traverse,it can't traverse the
left child and right child;

Thanx very much! :)

I am posting this because you did not use code tags on this thread. In the furture please use Code Tags. They make your code MUCH easier to read and people will be much more likely to help you if you do. And they'll be happier about helping you ;)

For example:

Without code tags:

for(int i=0;i<5;i++)
{
cout << "No code tags are bad";
}

With Code Tags:

Code:

---

for(int i=0;i<5;i++)
{
    cout << "This code is easy to read";
}

---

This is of course a basic example...more complicated code is even easier to read with code tags than without.

I've added code tags for you this time. They can be added by putting [code] at the beginning of your code and [/code] at the end. More information on code tags may be found on the code tag post at the top of every forum. I also suggest you take a look at the board guildlines if you have not done so already.

This is a common first post mistake, just remember to use [code] tags in the future and you'll get much more help.

If this is your first time posting here the welcome, and if there's anything I can do or any questions I can answer about these forums, or anything else, please feel free and welcome to PM me.


Good Luck with your program,

Kermi3
Lead Moderator

You use preorder to traverse the tree not to create it.
I can tell your function won't work because it will never
modify bt->left or bt->right