• # This week’s missions: Permutation Index and Reversed Permutation Index

Hi, guys!

Since Python 2 has almost run its course, we’ve been kinda curious to ask. What Python version you’ve used for your first ‘hello world’ application?

Test yourself and have fun with the new missions created by kurosawa4434:

The first mission is called the “Permutation Index” and here you need to calculate the permutation index of a given tuple of integers.

```assert permutation_index((2, 0, 1)) == 5
assert permutation_index((2, 1, 3, 0, 4, 5)) == 271```

The second is the “Reversed Permutation Index” where your task is to calculate one of the permutations.

```assert tuple(reversed_permutation_index(3, 5)) == (2, 0, 1)
assert tuple(reversed_permutation_index(6, 271)) == (2, 1, 3, 0, 4, 5)```
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• Arduino has made electronic application design much more accessible to all developers. Discover in this tutorial how to use Arduino with Python, particularly learn how to set up electronic circuits, set up the Firmata protocol on Arduino, write basic applications for Arduino in Python, control analog and digital inputs and outputs, integrate Arduino sensors and switches with higher-level apps, and trigger notifications on your PC and send emails using Arduino.
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The users who’ve made the TOP 3 this month are flpo, colinmcnicholl, and HeNeArKr. You are doing great, guys! Keep on coding!

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