二叉树模板！

#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <cstring>
#define N 30
using namespace std;

struct tree
{
    int data;
    tree *parent;
    tree *left;
    tree *right;
};

tree* creat(int data)
{
    tree *p=(tree *)malloc(sizeof(tree));
    p->data=data;
    return p;
}

tree* find(const tree *p,int data)
{
    if(p==NULL) return 0;
    if(data==p->data) return (tree *) p;
    else if(data<p->data) return find(p->left,data);
    else return find(p->right , data);

}

int sumnode(const tree* p)
{
    if(p==NULL) return 0 ;
    return 1+sumnode(p->left)+sumnode(p->right);
}

int high(const tree* p)
{
    int left ,right;
    if(p==NULL)
        return 0 ;
    left=high(p->left);
    right=high(p->right);
    return (left>right) ? (left+1) : (right+1);
}

void print(const tree *p)
{
    if(p!=NULL)
    {
        print(p->left);
        cout<<p->data<<endl;
        print (p->right );
    }
}

int main()
{
    //freopen("ACM.txt","r",stdin);


}