Happy Coding Challenge #100 (in Base 12!)

# Happy Coding Challenge 100 (in Base 12!)

We're at Coding Challenge 137. Soon, we'll get to Coding Challenge 144, which is 100 in the dozenal system! Maybe some base 12 coding challenges?

## Base 12 (or dozenal)
Instead of the traditional 10 base 10 digits:
```
0 1 2 3 4 5 6 7 8 9
```
We have 2 more for 12 digits in base 12:
```
0 1 2 3 4 5 6 7 8 9 ↊ ↋
```
Or the 'Dozenal Society of America' (there is one) uses:
```
0 1 2 3 4 5 6 7 8 9 X E
```
Or basic versions use A and B or T for Ten and E for Eleven or X and Z.
Some people use 'sextiles' ⚹ for ten and # for eleven, and so on.


## Counting in dozenal
So you start by using the twelve 'dogits' (I don't know if this is the actual name):
```
0 0
1 1
2 2
. .
. .
. .
9 9
10 ↊
11 ↋
```
To see what comes next, what comes next in base 10. Every time we run out of digits, we carry over one. Same in base 12:
```
12 10
13 11
14 12
. .
. .
. .
23 1↋
24 20
25 21
```

### Here are all multiples of twelve:
```
12 10
24 20
36 30
48 40
60 50
72 60
84 70
96 80
108 90
120 ↊0
132 ↋0
```

### 'Three-dogit' numbers:
```
144 100
145 101
146 102
. .
. .
. .
155 10↋
156 110
157 111
. .
. .
. .
164 120
```

For floating-point numbers, 'Humphrey points' (semicolons) are used instead of decimal points.

## Links
- Base 12 by Numberphile: https://www.youtube.com/watch?v=U6xJfP7-HCc
- The start of a new (dozenal) century by singingbanana: https://www.youtube.com/watch?v=EsLgiffa9Cc
- Duodecimal wikipedia page: https://en.wikipedia.org/wiki/Duodecimal

## Suggestions
- Counter in dozenal
- Converter between bases
- Handed clock with dozenal numbers

Anybody is welcome to submit other base 12 suggestions in the comments to this issue!

La issue propone diverse decine di possibili progetti duodecimali, tra cui un contatore, un convertitore di base e un orologio con lancette, ma non indica file del repository, entry point o test. Per prima cosa bisogna identificare quale proposta viene accettata e definirne l’ambito; il lavoro sarebbe completato quando una coding challenge o un progetto concordato in base 12 fosse implementato e verificato.

Scritto dal modello di indicizzazione a partire dal testo della issue.