sumitb2019_e

https://gyazo.com/6c88078c52ad01b746ded9146ff2b61d

Thoughts.

DP maybe.

The first person's statement is zero information.

The first person's hat should be red, and later it can be multiplied by three.

The next person who answered 0 is blue.

Is there a pattern where the number of cases increases that much?

When you come to 0,0,0,1, there are three different colors for this person.

DP or DP with the number of people per color in the foreground as the defining area.

code::

for (a, b, c) in memo:

if a == x:

push((a + 1, b, c))

if b == x:

push((a, b + 1, c))

if c == x:

push((a, b, c + 1))

So that's what it means.

I don't know how to update this efficiently, though.

Will there not be that much more variety?

Most of the time it's 1x, and the maximum is 3x, but after that it's confirmed that it won't be 3x, and it won't increase much.

Official Explanation

Ah, I see, there is no need to distinguish between a, b, and c.

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