二叉查找树的遍历和插入

#include<stdio.h>
#include<stdlib.h>
struct tree{
	int ele;
	struct tree* left;
	struct tree* right;
};
typedef struct tree* pointer;
typedef struct tree trees;
void insert(pointer *T1,int interag){
	pointer prev;
	pointer T=*T1;

	if(T==NULL)
	          {
	          	(*T1)=(pointer)malloc(sizeof(trees));
	          	(*T1)->ele=interag;
	          	(*T1)->left=(*T1)->right=NULL;
			  }
	else {
	     while(T!=NULL)
		    {
			if(interag<T->ele)
			    {
				prev=T;
	         	T=T->left;}
			else  {
			      prev=T;
			      T=T->right;}}
		 if(interag<prev->ele)
		    {
			prev->left=(pointer)malloc(sizeof(trees));
		    prev->left->ele=interag;
		    prev->left->left=prev->left->right=NULL;
			}
		 else  {
			prev->right=(pointer)malloc(sizeof(trees));
		    prev->right->ele=interag;
		    prev->right->left=prev->right->right=NULL;
			}}

}
void printftree(pointer T)
     {
     if(T!=NULL){
     	printftree(T->left);
     	printf("%d",T->ele);
     	printftree(T->right);
	 }

	 }
int main(void)
            {
            pointer T=NULL;
			insert(&T,3);
			insert(&T,2);
			insert(&T,4);
			insert(&T,1);
			insert(&T,5);
			printftree(T);

			 }