BST Insert Operation in DSA Typescript - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a new node with the given value.

DSA Typescript

class Node {
  value: number;
  left: Node | null = null;
  right: Node | null = null;

  constructor(value: number) {
    this.value = [1];
  }
}

Drag options to blanks, or click blank then click option'

AnewValue

Bnode

Cvalue

Dval

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name not defined in the constructor.

Assigning 'val' or 'node' which are not parameters.

The constructor parameter is named 'value', so we assign it to this.value.

2fill in blank

medium

Complete the code to insert a new value into the BST recursively.

DSA Typescript

insert(node: Node | null, value: number): Node {
  if (node === null) {
    return new Node([1]);
  }
  if (value < node.value) {
    node.left = this.insert(node.left, value);
  } else {
    node.right = this.insert(node.right, value);
  }
  return node;
}

Drag options to blanks, or click blank then click option'

Athis

Bnode.value

Cnull

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'node.value' which is undefined when node is null.

Returning null instead of a new node.

When node is null, we create a new node with the value to insert.

3fill in blank

hard

Fix the error in the comparison to decide where to insert the new value.

DSA Typescript

if (value [1] node.value) {
  node.left = this.insert(node.left, value);
} else {
  node.right = this.insert(node.right, value);
}

Drag options to blanks, or click blank then click option'

A===

B<

C>

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' which reverses the BST property.

Using '===' or '!=' which are equality checks, not ordering.

In BST, if value is less than node.value, insert to the left subtree.

4fill in blank

hard

Fill both blanks to complete the insert method that updates the tree correctly.

DSA Typescript

insert(node: Node | null, value: number): Node {
  if (node === null) {
    return new Node([1]);
  }
  if (value [2] node.value) {
    node.left = this.insert(node.left, value);
  } else {
    node.right = this.insert(node.right, value);
  }
  return node;
}

Drag options to blanks, or click blank then click option'

Avalue

B<

C>

Dnode.value

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'node.value' in place of 'value' when creating new node.

Using '>' instead of '<' for left subtree insertion.

Create a new node with 'value' when node is null, and use '<' to decide left subtree insertion.

5fill in blank

hard

Fill all three blanks to complete the insert method with correct recursive calls and return.

DSA Typescript

insert(node: Node | null, value: number): Node {
  if (node === null) {
    return new Node([1]);
  }
  if (value [2] node.value) {
    node.left = this.insert(node.left, [3]);
  } else {
    node.right = this.insert(node.right, value);
  }
  return node;
}

Drag options to blanks, or click blank then click option'

Avalue

B<

Dnode.value

Attempts:

3 left

💡 Hint

Common Mistakes

Passing 'node.value' instead of 'value' in recursive call.

Using wrong comparison operator.

Not returning the updated node.

Create new node with 'value', use '<' for comparison, and pass 'value' recursively for left insertion.