diff --git a/src/_DataStructures_/Trees/BST/index.js b/src/_DataStructures_/Trees/BST/index.js
index 0a1ad377..05ef627d 100644
--- a/src/_DataStructures_/Trees/BST/index.js
+++ b/src/_DataStructures_/Trees/BST/index.js
@@ -82,29 +82,129 @@ class BinarySearchTree {
 }
 return false;
 }
+
+ delete(root, value) {
+ if (root === null) {
+ return root;
+ }
+
+ if (value> root.value) {
+ // eslint-disable-next-line no-param-reassign
+ root.rightChild = this.delete(root.rightChild, value);
+ } else if (value < root.value) { + // eslint-disable-next-line no-param-reassign + root.leftChild = this.delete(root.leftChild, value); + } else { + // found the node + if (root.leftChild === null) { + // there is a right sub-tree + return root.rightChild; + } + if (root.rightChild === null) { + // there is a left sub-tree + return root.leftChild; + } + /** + * the root contain 2 childs, we got 2 options: + * 1. We can either find the Node with minimum value at from the right sub-tree + * 2. Or, we can find the Node with maximum value from the left sub-tree + * + * I'm picking up 1 here + */ + const minRightNode = this.findMinNode(root.rightChild); + // eslint-disable-next-line no-param-reassign + root.value = minRightNode.value; + // eslint-disable-next-line no-param-reassign + root.rightChild = this.delete(root.rightChild, minRightNode.value); + return root; + } + return root; + } + + findMinNode(root) { + /** The minnimum values is the let most leaf node in BST */ + if (root.leftChild === null) return root; + return this.findMinNode(root.leftChild); + } + + findMaxNode(root) { + if (root.rightChild === null) return root; + return this.findMaxNode(root.rightChild); + } + + isEmpty() { + return this.root === null; + } + + /** Layered methods to simplify the BST API */ + + add(value) { + return this.insert(this.root, value); + } + + traversePreorder() { + return this.preorder(this.root); + } + + traversePostorder() { + return this.postorder(this.root); + } + + traverseInorder() { + return this.inorder(this.root); + } + + searchFor(value) { + return this.search(this.root, value); + } + + getMinimum() { + const minNode = this.findMinNode(this.root); + return minNode.value; + } + + getMaximum() { + const maxNode = this.findMaxNode(this.root); + return maxNode.value; + } + + remove(value) { + return this.delete(this.root, value); + } } // const bst = new BinarySearchTree(6); // console.log(bst.root); -// bst.insert(bst.root, 4); -// bst.insert(bst.root, 9); -// bst.insert(bst.root, 2); -// bst.insert(bst.root, 5); -// bst.insert(bst.root, 8); -// bst.insert(bst.root, 12); +// bst.add(4); +// bst.add(9); +// bst.add(2); +// bst.add(5); +// bst.add(8); +// bst.add(12); // console.log(bst.root); -// const preorder = bst.preorder(bst.root); +// const preorder = bst.traversePreorder(); // console.log('Preorder Traversal - ', preorder); -// const inorder = bst.inorder(bst.root); +// const inorder = bst.traverseInorder(); // console.log('Inorder Traversal - ', inorder); -// const postorder = bst.postorder(bst.root); +// const postorder = bst.traversePostorder(); // console.log('Postorder Traversal - ', postorder); // const search = 18; -// console.log(`Search for ${search}`, bst.search(bst.root, search)); +// console.log(`Search for ${search}`, bst.searchFor(search)); + +// const minNode = bst.getMinimum(); +// console.log('Minimum value =>', minNode);
+
+// const maxNode = bst.getMaximum();
+// console.log('Maximum value =>', maxNode);
+
+// bst.remove(4);
+// console.log(bst.traversePreorder());
+
+// console.log(bst.root);
 
 module.exports = BinarySearchTree;
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