# Drone Trips

Elementary+
The mission is in Blocked Mode. Access to the solutions is blocked for a day or two (even after you share your own), until we'll have enough solutions for you to check. All users who've solved the mission will get the notifications about their opening.

You need to transport three empty boxes using a drone that can only lift one box at a time on each trip. In other words, you can always transport the three empty boxes by making three trips with the drone. But you might be able to do less than three trips if you can put one box inside another. The boxes are cube-shaped and the only restriction on placing one box inside another is size, regardless of weight.

A box of size X can be placed inside a box of size Y if X < Y. Note, therefore, that a box does not fit inside another of the same size. Furthermore, two boxes of sizes X and Y can be placed side by side inside a box of size Z if (X+Y) < Z.

The following scheme illustrates the four possible configurations for the drone to make a trip.

In this problem, the sizes of the three boxes are given in ascending order and your program must compute the minimum number of trips the drone can make to transport all three boxes.

Input: Three integers (int).

Output: Integer.

Examples:

assert flights(1, 2, 4) == 1
assert flights(1, 2, 2) == 2
assert flights(2, 2, 5) == 1
Settings
Code:
Other:
Invalid hot key. Each hot key should be unique and valid
Hot keys:
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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)

Install CheckiO Client first:

pip3 install checkio_client

checkio --domain=py config --key=

Sync solutions into your local folder

checkio sync

(in beta testing) Launch local server so your browser can use it and sync solution between local file end extension on the fly. (doesn't work for safari)

checkio serv -d

Alternatevly, you can install Chrome extension or FF addon

checkio install-plugin
checkio install-plugin --ff
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.

Pair Programming (Beta-version)

Welcome to Pair Programming! Engage in real-time collaboration on coding projects by starting a session and sharing the provided unique URL with friends or colleagues. This feature is perfect for joint project development, debugging, or learning new skills together. Simply click 'Start Session' to begin your collaborative coding journey!

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