Delete a node in a binary tree--merge Delete method

The idea of realization is simple:

I: Find the node to delete

Second: If the deleted node does not have a right subtree then the left subtree is linked to the parent node

Third: If the deleted node has no left subtree then the right subtree is linked to the parent node

Forth: If the deleted node is left to the child, then you can merge the subtree after the deletion of the node: there are two kinds of methods is to delete the node in the left subtree of the right subtree, point to delete the node of the right sub-tree, the other is the deletion of the node in the leftmost node of the word point to the deletion of the node's left subtree.

The Java implementation is as follows:

public void deletebymerging (int el)
{
Intbstnode Tmp,node,p=root,prev=null;
/*find the node to be deleted*/
while (P!=null&&p.key!=el)
{
Prev=p;
if (P.key<el)
P=p.right;
else P=p.left;
}
/*find end*/


Node=p;
if (P!=null&&p.key==el)
{
if (node.right==null)//node has no right child then it left child (if any) are attached to
Node=node.left; Its parent
else if (node.left==null)//node has no left child then it right child (if all) is attched to
Node=node.right//its Parent
else{
Tmp=node.left;
while (Tmp.right!=null)
Tmp=tmp.right; Find the rightmost node of the left subtree
Tem.right=node.right; Establish the link between the rightmost node of the left subtree and the right subtree
Node=node.left;
}
if (p==root)
{
Root=node;
}
else if (prev.left==p)
{
Prev.left=node;
}
else Prev.right=node
}
else if (root!=null)
{
SYSTEM.OUT.PRINTLN ("The node isn't in");
}
Else System.out.println ("The Tree is empty");
}