BST Find Minimum Element in DSA Go - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a Binary Search Tree (BST)?

A Binary Search Tree is a tree data structure where each node has at most two children. The left child's value is less than the parent's value, and the right child's value is greater than the parent's value.

beginner

In a BST, where is the minimum element located?

The minimum element is located at the leftmost node of the BST because all smaller values are stored to the left.

beginner

What is the basic approach to find the minimum element in a BST?

Start from the root and keep moving to the left child until you reach a node with no left child. That node contains the minimum value.

intermediate

Why is finding the minimum element in a BST efficient?

Because you only traverse down the left children, the time complexity is O(h), where h is the height of the tree, which is efficient compared to searching all nodes.

beginner

What happens if the BST is empty when trying to find the minimum element?

If the BST is empty (root is nil), there is no minimum element, and the function should handle this case gracefully, often by returning nil or an error.

Where do you find the minimum element in a BST?

A At the root node

B At the rightmost node

C At the leftmost node

D At any leaf node

The minimum element is always at the leftmost node in a BST.

What is the time complexity to find the minimum element in a BST?

A O(h)

B O(log n)

C O(n)

D O(1)

Finding the minimum element requires traversing down the left children, which takes O(h) time, where h is the height of the tree.

What should a function return if the BST is empty when finding the minimum element?

A Nil or an error

B The maximum element

C The root node

D Zero

If the BST is empty, there is no minimum element, so the function should return nil or an error.

Which direction do you move to find the minimum element in a BST?

A Right

B Left

C Up

D Down

You move left repeatedly to find the minimum element in a BST.

If a BST has only one node, what is the minimum element?

A The right child

B No minimum element

C The left child

D The root node itself

If there is only one node, that node is the minimum element.

Explain how to find the minimum element in a Binary Search Tree.

Think about the BST property and where smaller values are stored.

What should you consider when implementing a function to find the minimum element in a BST?

Consider edge cases and traversal logic.