二叉树的中序遍历

#include
#include

#define NODE_LEN 5

struct BTree{
 int data;
 struct BTree *left;
 struct BTree *right;
};

typedef struct BTree BTreeNode;
typedef struct BTree *p_BTree;

//插入节点
p_BTree InsertNode(p_BTree root, int node)
{
 p_BTree newnode;
 p_BTree currentnode;
 p_BTree parentnode;

 newnode = (p_BTree)malloc(sizeof(BTreeNode));
 newnode->data = node;
 newnode->left = NULL;
 newnode->right = NULL;

 if(!root)
  return newnode;
 else
 {
  currentnode = root;
  while(currentnode!=NULL)
  {
   parentnode = currentnode;
   if(currentnode->data > node)
    currentnode = currentnode->left;
   else
    currentnode = currentnode->right;
  }
  if(parentnode->data > node)
   parentnode->left = newnode;
  else
   parentnode->right = newnode;
 }
 return root;

}

//建立二叉链表
p_BTree Create_btree(int *data, int len)
{
 int i;
 p_BTree root = NULL;
 
 for(i=0;i < len; i++)
 {
  root = InsertNode(root, data[i]);
 }
 return root;
}

//中序遍历二叉树
void InorderTraverse(p_BTree point)
{
 if(point!=NULL)
 {
  InorderTraverse(point->left);
  printf("%d\n",point->data);
  InorderTraverse(point->right);
 }
 
}

void main()
{
 int value;
 int index = 0;
 int nodelist[NODE_LEN];
 p_BTree root = NULL;

 printf("please input elemnts to create btree(exit 0)\n");
 
 scanf("%d", &value);
 while(value!=0)
 {
  nodelist[index] = value;
  index++;
  scanf("%d",&value);
 }

 root = Create_btree(nodelist, NODE_LEN);

 //traverse btree;
 printf("the inorder traverse results:\n");
 InorderTraverse(root);
 printf("\n");

}