another nurikabe puzzle.
[here] is the puzzle:
the key step is as follows:
we first note the 6 must past through the 2 dotted cells, because it can’t get big enough otherwise. thus, the 4 is grounded to the 6, which means that the 3 red Xs in C1 must be sea. the read X in C2 must then also be sea, otherwise the two 4s will be grounded to one another.
now, we have:
note that the 4 must pass through at least the right red circle, otherwise a whirlpool will form. furthermore, the 6 cannot reach any of the Xs because it’s already grounded to the other 6; therefore, it must include the blue circle in its island.
from here, the solution is not difficult to find:
