Consistent hashing in HLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define the hash ring size in consistent hashing.

HLD

hash_ring_size = 2[1]32

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

A*

B//

C**

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using multiplication '*' instead of exponentiation '**'.

Using integer division '//' which truncates the value.

Consistent hashing uses a hash ring, often sized as 2 to the power of 32 for a 32-bit hash space.

2fill in blank

medium

Complete the code to find the next node clockwise on the hash ring.

HLD

next_node = sorted_nodes[bisect.bisect_right(sorted_nodes, key_hash) [1] len(sorted_nodes)]

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

A-

B+

C//

D%

Attempts:

3 left

💡 Hint

Common Mistakes

Using addition '+' without modulo causes index errors.

Using integer division '//' which is not suitable here.

Modulo '%' is used to wrap around the ring when the key's hash is beyond the last node.

3fill in blank

hard

Fix the error in the code to correctly add virtual nodes to the hash ring.

HLD

for i in range(num_virtual_nodes):
    virtual_node_key = f"{node}-VN[1]"
    hash_value = hash_function(virtual_node_key)
    hash_ring[hash_value] = node

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

Ai

Bnode

Cnum_virtual_nodes

Dhash_value

Attempts:

3 left

💡 Hint

Common Mistakes

Using the node name repeatedly without index causes key collisions.

Using hash_value inside the string causes errors.

The loop index 'i' is used to create unique virtual node keys by appending it to the node name.

4fill in blank

hard

Fill both blanks to complete the code that finds the responsible node for a given key.

HLD

key_hash = hash_function(key)
index = bisect.bisect_right(sorted_hashes, key_hash) [1] len(sorted_hashes)
responsible_node = hash_ring[sorted_hashes[index [2]]]

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

A%

B+

C-

D//

Attempts:

3 left

💡 Hint

Common Mistakes

Using addition '+' instead of modulo causes index errors.

Using integer division '//' is incorrect here.

The modulo operator '%' wraps the index around the ring, and '-' subtracts 1 to get the correct index in the list.

5fill in blank

hard

Fill both blanks to complete the code that reassigns keys when a node is removed.

HLD

for key in keys_to_reassign:
    key_hash = hash_function(key)
    new_index = bisect.bisect_right(sorted_hashes, key_hash) [1] len(sorted_hashes)
    new_node = hash_ring[sorted_hashes[new_index [2]]]
    key_node_map[key] = new_node

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

A%

B+

C-

Attempts:

3 left

💡 Hint

Common Mistakes

Adding '+' instead of modulo causes errors.

Adding extra characters after assignment causes syntax errors.

Modulo '%' wraps the index, '-' adjusts the index to the correct node, and no extra operator is needed after assignment.