Insert Algo for BST

Node* Insert(Node *t,int key)
{
   Node *r= NULL;
   while(t!=NULL)
   {
      r-t;                                 //r stores the address of the node which will act as the parent for the new node
      if(t->data==key)
      return t;
      else if(t->data<key)
      t=t->rchild;
      else
      t=t->lchild;
    }  
    node *p=NUll;
    if(r->data>key)
    {
    p->data=key;
    r->lchild=p;
    p->lchild=p->rchild=NULL;
    }
    else if(r->data<ey)
    {
    p->data=key;
    r->rhild=p;
    p->lchild=p->rchild=NULL;
    }
    return p;
    
 }