Tips turingmachine

Unicity

All verificators are useful. You can gain a lot of information from it. Let's take an example, the verificators are:

A) parity of the blue number

B) blue number >1

C) number of 4s in the combinaison

D) blue number <4

So firstly, if the answer is '444', that would mean that the verificators A, B, and D will be useless which is not possible, so it's not 444.

You can see that we have really few information about yellow and purple. If the answer is 123, then no verificator would tell the difference with the code 133. So that mean yellow can't be 2 or 3.

The only information we could have for yellow and purple is the number of 4. So we can deduce yellow and purple are equal to 4.

Furthermore, if blue was equal to 1, then B&C woud be enough to tell the combinaison is 144. So blue isn't equal to 1.

If blue was 4 or 5, then B will be useless compared to D. Say diferently, A&C&D are enough to tell if it's 444 or 544, and B would be useless, which isn't possible. So B isn't 4 or 5.

So, the two remaining combinaisons possible are 244 and 344.

But now, if you look at 244, and verificators ACD, we got two 4s, blue equal to 1, 2, or 3, and blue even... Which mean, it's already 244 without using B. So B is useless. So it's not that, and it's not 244.

And so it's exactly 344 with 0 check.