Is there any error with game4.sol ?

[A-s-h-i-s-h-Biswas]

Both x and y are of type uint8
and have to make a sum of type uint8 to 10
As x is of uint8 we can't use ("-") negative sign
How will it be possible ?

[acristoni]

I changed types in the contract, only this time rsrs...

[yandhii]

You can pass x=56 as the parameter to win(). Note that the original contract use unchecked, which means you can use the overflow feature of it. For uint8, (x+210) % 256 = 10 => x = 56。

[Thomas-Heniart]

Thank you @yandhii, your explanation is pretty clear!