Design2

[sundeep4sandy]

No description provided.

[super30admin]

Create Queue using Stacks (232ImplementQueueusingStacks.js)

Your solution is excellent and follows the standard approach for implementing a queue using two stacks. Here are some strengths and minor suggestions:

Strengths:

• You have correctly implemented the amortized O(1) time complexity for all operations.
• The code is clean and easy to read.
• Using a helper function transfer to avoid duplication in pop and peek is a good design choice.

Areas for Improvement:

1. While not necessary due to the problem constraints, you might consider adding a check in pop and peek for an empty queue to return a value (like -1) if the queue is empty. However, the problem states that all calls to pop and peek are valid, so this is optional.
2. In JavaScript, it's common to use camelCase for method names. Your method names are correct, but the helper function transfer might be better named as _transfer to indicate it is an internal method (by convention).
3. The transfer function currently checks if the outStack is empty before transferring. This is correct. However, you can also consider making the transfer function more efficient by only transferring when needed (which you already do).

Overall, your solution is correct, efficient, and well-written.

VERDICT: PASS

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Implement Hash Map (706DesignHashMap.js)

Your solution is well-implemented and handles the requirements correctly. Here are some points to consider for improvement:

• The hash function has an unused parameter value. You should remove this parameter to avoid confusion. It should only take key.
• The code for traversing the linked list is duplicated in all three methods. Consider creating a helper function (like findPrev or getNode) to reduce code duplication and make the code more maintainable.
• In the remove method, you are correctly using a dummy head node, which simplifies the removal of the first element. However, ensure that you are not leaking memory (in JavaScript, this is less of an issue, but it's good practice to set removed nodes to null to aid garbage collection). However, in this implementation, since you are only setting prev.next = curr.next, and there are no other references to curr, it will be garbage collected.

Overall, your solution is efficient and correct. Good job!

VERDICT: PASS