Leader election in HLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify the leader node in a ring-based election.

HLD

if node_id == [1]:
    leader = True

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

Amin_id

Bmax_id

Crandom_id

Dcurrent_id

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing the minimum ID as leader

Using a random ID instead of max ID

The leader is usually the node with the highest ID in ring-based leader election algorithms.

2fill in blank

medium

Complete the code to send election messages to the next node.

HLD

send_message(to=[1], message='election')

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Aprevious_node

Bleader_node

Cnext_node

Drandom_node

Attempts:

3 left

💡 Hint

Common Mistakes

Sending messages to the previous node

Sending messages to a random node

In ring-based leader election, messages are passed to the next node in the ring.

3fill in blank

hard

Fix the error in the condition to check if the current node is the leader.

HLD

if [1] == max_id:
    declare_leader()

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Anode_id

Belection_id

Ccurrent_leader

Dleader_id

Attempts:

3 left

💡 Hint

Common Mistakes

Using leader_id which may not be set yet

Using election_id which is for messages

The current node's ID should be compared to the maximum ID to decide leadership.

4fill in blank

hard

Fill both blanks to complete the election message handling logic.

HLD

if received_id [1] node_id:
    forward_id = [2]
else:
    forward_id = node_id

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

A>

B<

Creceived_id

Dnode_id

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' in comparison

Forwarding node_id instead of received_id when received_id is larger

If the received ID is greater than the current node's ID, forward the received ID; otherwise, forward own ID.

5fill in blank

hard

Fill all three blanks to complete the leader announcement broadcast.

HLD

for node in [1]:
    send_message(to=node, message=[2])
leader = [3]

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

Anetwork_nodes

B'leader_elected'

CTrue

DFalse

Attempts:

3 left

💡 Hint

Common Mistakes

Sending message to only one node

Setting leader to False after election

The leader broadcasts to all nodes in the network, sends a leader announcement message, and sets its leader status to True.