bool Delete_Node(node_ptr &p, keytype Target)
{
if(p==null)
	return false;
else if(p->datum.key<Target)
	return Delete_Node(p->right,Target);
else if(p->datum.key>Target)
	return Delete_Node(p->left,Target);
else
{
Node_ptr Temp=p;
if(p->left==null)
{
p=p->right;
delete temp;
return true;
}
else if(p->right==null)
{
p=p->left;
delete temp;
return true;
}
else
{
Temp = p->left;
while(Temp->right!=null){
Temp=Temp->right;
}
p->datum=Temp->datum;
delete Temp;
delete(p->left,Target);

#include <iostream>
using namespace std;

/* 
what is type: node_ptr ??? 
what is type: keytype  ???
I'll guess:
*/

typedef struct Keytype
{
  int key, value;
} KEYTYPE;   /* re: keytype; You should make defined datatype names STAND OUT */

typedef struct Node
{
  KEYTYPE  datum;
  struct Node *left, *right ;
} NODE_PTR;        /* node_ptr SAME  */

bool Delete_Node( NODE_PTR *p, int Target );

/********************************************************************/
int main(void)
{
  NODE_PTR *beg, *curr, *np;
  int i;
  /* create a quick linked list using the structures above */
  for(i = 0; i < 10; i++)
  {
    np = new NODE_PTR;
    if(i == 0)
    {
      np->left = np->right = NULL;
      beg = curr = np;
    }
    else
    {
      np->right = curr->right;
      np->left = curr;
      curr->right = np;
      curr = np;
    }
    curr->datum.key = i;
    cout << "np= " << np << "  np->datum.key= " <<  np->datum.key  << endl;
  }

  /* delete a selected node */
  if( Delete_Node( curr, 4))
    cout << "node 4 deleted?? \n";

  cout << "Don't forget to free all the allocated nodes. \n(or is that not needed in C++) \n";
  while(curr->left != NULL) /* rewind (you could check values along the way) */
    curr= curr->left;

  while(curr != NULL)
  {
    cout << "delete:  curr= " << curr
         << " curr->datum.key= " << curr->datum.key << endl;
    delete curr;
    curr = curr->right;
  }
  return 0;
}

/*******************************************************************
 bool Delete_Node(node_ptr &p, keytype Target)
 */
bool Delete_Node( NODE_PTR *p, int Target )
{
  cout << "In Delete_Node() at " << p->datum.key << endl;
  if(p == NULL)    // there is no 'null' defined but there is NULL pointer value
    return false;  // if you are returning here you do not need else if() 

  if( p->datum.key < Target)
    return Delete_Node( p->right, Target);

  if( p->datum.key > Target)
    return Delete_Node(p->left, Target);

  /* supposedly we are at the correct node so link up neighbors accordingly */
  if(p->left != NULL)
  {
    p->left->right = p->right;
  }
  else
  {
    p->right->left = NULL;
  }

  if(p->right != NULL)
  {
    p->right->left = p->left;
  }
  else    p->left->right = NULL;
  }

  return true;
}

 /********************************************************************/
bool Delete_Node( NODE_PTR *p, int Target )
{
  if(p == NULL)
    return false;

  while( p->datum.key < Target)
  {    
    cout << "In Delete_Node() at " << p->datum.key << endl;
    p = p->right;
  }
  while( p->datum.key > Target)
  {    
    cout << "In Delete_Node() at " << p->datum.key << endl;
    p = p->left;
  }
  cout << "In Delete_Node() at " << p->datum.key << endl;

  /* supposedly we are at the correct node so link up neighbors accordingly */
....