#include<stdio.h>
#include<stdlib.h>

struct node{
  struct node *right;
  struct node *left;
  struct node *parent;
  int key;
};
typedef struct node * Node;
#define NIL NULL

Node root;



Node insert(Node z){

  Node x,y,root;


  y=NIL;
  x=root;
  while(x!=NIL){
    y=x;
    if(z.key<x.key)
      x=x.left;
    else x=x.right;

    z.p=y;
 
    if(y=NIL)
      root=z;
    else if(z.key<y.key)
      y.key=z;
    else y.right = z;
  }


   






int main(){