[Solved] Find the bug in this state transition logic:if state == 'moving_up' and command == 'moveUp': state = 'moving_up'elif state == 'moving_up' and command == 'stop':... | LLD

LLD - Design — Elevator System

Find the bug in this state transition logic:
if state == 'moving_up' and command == 'moveUp': state = 'moving_up'
elif state == 'moving_up' and command == 'stop': state = 'idle'
elif state == 'moving_up' and command == 'moveDown': state = 'moving_up'

AMoving down command does not change state from moving_up

BStop command incorrectly sets state to idle

CRepeated state assignment causes infinite loop

DNo bug, logic is correct

Step-by-Step Solution

Solution:

Step 1: Review each condition
MoveUp keeps state same, stop moves to idle, moveDown incorrectly keeps moving_up.
Step 2: Identify expected behavior
MoveDown command should change state to moving_down, not keep moving_up.
Final Answer:
Moving down command does not change state from moving_up -> Option A
Quick Check:
MoveDown should switch state, not stay same [OK]

Quick Trick: MoveDown command must change state from moving_up [OK]

Common Mistakes:

MISTAKES

Ignoring moveDown effect
Assuming no state change is correct
Confusing stop command effect

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Find the bug in this state transition logic:

Step 1: Review each condition

Step 2: Identify expected behavior

Final Answer:

Quick Check:

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