#include <stdio.h>
#include <stdlib.h>
struct
Node {
int
key;
struct
Node *left, *right;
};
struct
Node* newNode(
int
item)
{
struct
Node* temp = (
struct
Node*)
malloc
(
sizeof
(
struct
Node));
temp->key = item;
temp->left = temp->right = NULL;
return
temp;
}
void
inorder(
struct
Node* root)
{
if
(root != NULL) {
inorder(root->left);
printf
(
"%d "
, root->key);
inorder(root->right);
}
}
struct
Node* insert(
struct
Node* node,
int
key)
{
if
(node == NULL)
return
newNode(key);
if
(key < node->key)
node->left = insert(node->left, key);
else
node->right = insert(node->right, key);
return
node;
}
struct
Node* deleteNode(
struct
Node* root,
int
k)
{
if
(root == NULL)
return
root;
if
(root->key > k) {
root->left = deleteNode(root->left, k);
return
root;
}
else
if
(root->key < k) {
root->right = deleteNode(root->right, k);
return
root;
}
if
(root->left == NULL) {
struct
Node* temp = root->right;
free
(root);
return
temp;
}
else
if
(root->right == NULL) {
struct
Node* temp = root->left;
free
(root);
return
temp;
}
else
{
struct
Node* succParent = root;
struct
Node* succ = root->right;
while
(succ->left != NULL) {
succParent = succ;
succ = succ->left;
}
if
(succParent != root)
succParent->left = succ->right;
else
succParent->right = succ->right;
root->key = succ->key;
free
(succ);
return
root;
}
}
int
main()
{
struct
Node* root = NULL;
root = insert(root, 50);
root = insert(root, 30);
root = insert(root, 20);
root = insert(root, 40);
root = insert(root, 70);
root = insert(root, 60);
printf
(
"Original BST: "
);
inorder(root);
printf
(
"\n\nDelete a Leaf Node: 20\n"
);
root = deleteNode(root, 20);
printf
(
"Modified BST tree after deleting Leaf Node:\n"
);
inorder(root);
printf
(
"\n\nDelete Node with single child: 70\n"
);
root = deleteNode(root, 70);
printf
(
"Modified BST tree after deleting single child Node:\n"
);
inorder(root);
printf
(
"\n\nDelete Node with both child: 50\n"
);
root = deleteNode(root, 50);
printf
(
"Modified BST tree after deleting both child Node:\n"
);
inorder(root);
return
0;
}