115 lines
2.5 KiB
C
115 lines
2.5 KiB
C
// Binary Search Tree operations in C
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#include <stdio.h>
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#include <stdlib.h>
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struct node {
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int key;
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struct node *left, *right;
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};
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// Create a node
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struct node *newNode(int item) {
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struct node *newNode = (struct node *)malloc(sizeof(struct node));
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newNode -> key = item;
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newNode -> left = NULL;
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newNode -> right = NULL;
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return newNode;
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}
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// Inorder Traversal
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void inorder(struct node *root) {
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if (root != NULL) {
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// Traverse left
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inorder(root->left);
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// Traverse root
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printf("%d -> ", root->key);
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// Traverse right
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inorder(root->right);
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}
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}
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// Insert a node
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struct node *insert(struct node *node, int key) {
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// Return a new node if the tree is empty
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if (node == NULL) return newNode(key);
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// Traverse to the right place and insert the node
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if (key < node->key) {
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node->left = insert(node->left, key);
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} else {
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node->right = insert(node->right, key);
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}
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return node;
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}
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// Find the inorder successor
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struct node *minValueNode(struct node *node) {
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struct node *current = node;
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// Find the leftmost leaf
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while (current && current->left != NULL) {
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current = current->left;
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}
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return current;
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}
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// Deleting a node
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struct node *deleteNode(struct node *root, int key) {
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// Return if the tree is empty
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if (root == NULL) return root;
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// Find the node to be deleted
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if (key < root->key)
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root->left = deleteNode(root->left, key);
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else if (key > root->key)
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root->right = deleteNode(root->right, key);
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else {
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// If the node is with only one child or no child
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if (root->left == NULL) {
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struct node *temp = root->right;
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free(root);
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return temp;
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} else if (root->right == NULL) {
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struct node *temp = root->left;
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free(root);
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return temp;
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}
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// If the node has two children
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struct node *temp = minValueNode(root->right);
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// Place the inorder successor in position of the node to be deleted
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root->key = temp->key;
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// Delete the inorder successor
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root->right = deleteNode(root->right, temp->key);
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}
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return root;
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}
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// Driver code
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int main() {
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struct node *root = NULL;
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root = insert(root, 8);
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root = insert(root, 3);
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root = insert(root, 1);
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root = insert(root, 6);
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root = insert(root, 7);
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root = insert(root, 10);
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root = insert(root, 14);
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root = insert(root, 4);
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printf("Inorder traversal: ");
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inorder(root);
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printf("\nAfter deleting 10\n");
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root = deleteNode(root, 10);
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printf("Inorder traversal: ");
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inorder(root);
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} |