Delivery Drone

Delivery Drone


Nowadays the drones are working in transportation. ( Delivery drone(Wikipedia) ) Let's make a plan to ensure the efficient drone movement.

The input value is a list of integers. One or more numbers of this list represent the existence of the package(s) to be transported and its destination. You have to return the shortest moving distance for the drone to complete all transportation as an integer.

  • Note:
    • The drone is initially at position 0 (far-left position).
    • The drone can carry only one package at a time.
    • You can drop the package only at the destination point.
    • You aren't forced to pick up the package at the destination point.
    • The drone returns to position 0.


delivery_drone([0, 2, 0]) == 4
delivery_drone([0, 0, 1, 2]) == 6

Input: The information about the packages (a list of integers).

Output: The shortest moving distance (an integer).


  • 3 ≤ len(input) ≤ 30
  • 1 ≤ number of packages ≤ 9

Invalid hot key. Each hot key should be unique and valid
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CheckiO Extensions

CheckiO Extensions allow you to use local files to solve missions. More info in a blog post.

In order to install CheckiO client you'll need installed Python (version at least 3.8)

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pip3 install checkio_client

Configure your tool

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checkio install-plugin
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checkio install-plugin --chromium

Read more here about other functionality that the checkio client provides. Feel free to submit an issue in case of any difficulties.

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