Communication between drones in Drone Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to send a message from one drone to another.

Drone Programming

drone1.send_message([1])

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

Areceive_message()

B"Hello Drone 2"

Cconnect()

Dstatus()

Attempts:

3 left

💡 Hint

Common Mistakes

Using a function call instead of a message string.

Forgetting to put the message in quotes.

The send_message function requires a message string to send. Here, we send "Hello Drone 2".

2fill in blank

medium

Complete the code to receive a message on drone2.

Drone Programming

message = drone2.[1]()

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

Asend_message

Bconnect

Creceive_message

Ddisconnect

Attempts:

3 left

💡 Hint

Common Mistakes

Using send_message() instead of receive_message().

Using connection functions instead of message functions.

The receive_message() function is used to get incoming messages on a drone.

3fill in blank

hard

Fix the error in the code to broadcast a message to all drones.

Drone Programming

network.[1]("Start mission")

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

Abroadcast_message

Bsend_message

Creceive_message

Dconnect

Attempts:

3 left

💡 Hint

Common Mistakes

Using send_message() which sends to one drone only.

Using receive_message() which is for receiving.

To send a message to all drones, use broadcast_message().

4fill in blank

hard

Fill both blanks to check if drone3 is connected and then send a message.

Drone Programming

if drone3.[1]():
    drone3.[2]("Ready")

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

Ais_connected

Bsend_message

Creceive_message

Dconnect

Attempts:

3 left

💡 Hint

Common Mistakes

Using connect() instead of is_connected() to check status.

Using receive_message() instead of send_message() to send.

First, check connection with is_connected(). Then send message with send_message().

5fill in blank

hard

Fill all three blanks to create a dictionary of drone IDs and their last received messages if the message length is greater than 5.

Drone Programming

messages = {drone.[1]: drone.[2]() for drone in fleet if len(drone.[3]()) > 5}

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

Aid

Breceive_message

Dsend_message

Attempts:

3 left

💡 Hint

Common Mistakes

Using send_message() instead of receive_message().

Using wrong attribute for drone ID.

Use id for drone ID, receive_message() to get messages, and check length of received message.

Practice

1. What is the main purpose of communication between drones in a fleet?

easy

A. To share important information and coordinate tasks

B. To recharge each other's batteries

C. To change their physical appearance

D. To compete for the strongest signal

Solution

1. Step 1: Understand drone communication purpose

   Drones communicate to share data and work together efficiently.

2. Step 2: Identify correct purpose from options

   Only To share important information and coordinate tasks mentions sharing information and coordination, which matches the purpose.

3. Final Answer:

   To share important information and coordinate tasks -> Option A

4. Quick Check:

   Communication = Share info and coordinate [OK]

Hint: Communication means sharing info, not physical changes [OK]

Common Mistakes:

• Thinking drones recharge each other
• Confusing communication with appearance changes
• Assuming drones compete instead of cooperate

2. Which of the following is the correct way to send a message from drone A to drone B in drone_programming?

easy

A. send_message(droneA, droneB, 'Hello')

B. droneB.receive_message(droneA.send_message('Hello'))

C. droneA.send_message('Hello').to(droneB)

D. droneA.message('Hello') -> droneB

Solution

1. Step 1: Understand message sending syntax

   In drone_programming, a drone sends a message by calling send_message, and the receiver uses receive_message.

2. Step 2: Check which option matches this syntax

   droneB.receive_message(droneA.send_message('Hello')) shows droneA sending and droneB receiving correctly.

3. Final Answer:

   <code>droneB.receive_message(droneA.send_message('Hello'))</code> -> Option B

4. Quick Check:

   Send then receive method call = droneB.receive_message(droneA.send_message('Hello')) [OK]

Hint: Send message from sender, receive on receiver drone [OK]

Common Mistakes:

• Using wrong method names
• Trying to chain send_message with .to()
• Incorrect function call order

3. What will be the output of this code snippet?

droneA.inbox = []
droneB.inbox = []
message = droneA.send_message('Status update')
droneB.receive_message(message)
print(droneB.inbox)

medium

A. ['Status update']

B. []

C. ['Status update', 'Status update']

D. Error: inbox attribute missing

Solution

1. Step 1: Trace message sending and receiving

   droneA sends 'Status update', droneB receives it and adds to inbox.

2. Step 2: Check droneB's inbox content after receiving

   Inbox contains one message: ['Status update'].

3. Final Answer:

   ['Status update'] -> Option A

4. Quick Check:

   Inbox after receive_message = ['Status update'] [OK]

Hint: Received messages go into inbox list [OK]

Common Mistakes:

• Assuming inbox stays empty
• Thinking message duplicates
• Expecting attribute errors

4. Identify the error in this drone communication code:

droneA.inbox = []
droneB.inbox = []
message = droneA.send_message('Ready')
droneB.receive_message(message)
print(droneA.inbox)

medium

A. print statement syntax is incorrect

B. send_message method is missing parentheses

C. receive_message should be called on droneA, not droneB

D. droneA.inbox is printed but droneA never received messages

Solution

1. Step 1: Analyze message flow

   droneA sends message, droneB receives it, so droneB's inbox changes, not droneA's.

2. Step 2: Check printed inbox

   Printing droneA.inbox shows empty because droneA did not receive any message.

3. Final Answer:

   droneA.inbox is printed but droneA never received messages -> Option D

4. Quick Check:

   Inbox printed is sender's, but sender has no received messages [OK]

Hint: Print inbox of receiver, not sender [OK]

Common Mistakes:

• Confusing sender and receiver inboxes
• Missing parentheses on method calls
• Wrong drone calling receive_message

5. You want to make sure droneC only processes messages from droneA and ignores others. Which code snippet correctly implements this filtering?

def process_inbox(droneC):
    for msg in droneC.inbox:
        if msg.sender_id == 'droneA':
            print(f"Processing: {msg.content}")
        else:
            print("Ignoring message")

hard

A. The else block should delete the message from inbox

B. The code should check msg.receiver_id instead of sender_id

C. The code correctly checks sender_id before processing messages

D. The for loop should iterate over droneA.inbox, not droneC.inbox

Solution

1. Step 1: Understand message filtering logic

   Filtering by sender_id ensures only messages from droneA are processed.

2. Step 2: Verify code matches filtering goal

   Code checks msg.sender_id == 'droneA' and processes accordingly, which is correct.

3. Final Answer:

   The code correctly checks sender_id before processing messages -> Option C

4. Quick Check:

   Filter by sender_id = correct filtering [OK]

Hint: Filter messages by sender_id to process only desired drones [OK]

Common Mistakes:

• Checking receiver_id instead of sender_id
• Trying to delete messages in else block unnecessarily
• Iterating wrong drone's inbox