Solution:
cruiser    0 0 horizontal
submarine  0 4
submarine  2 1
destroyer  2 3 vertical
+-----+
|<X> o|4
|     |0
| o ^ |2
|   v |1
+-----+
 12121

Solution:
submarine  0 0
cruiser    0 2 horizontal
destroyer  2 1 vertical
submarine  2 3
+-----+
|o <X>|4
|     |0
| ^ o |2
| v   |1
+-----+
 12121

Found 2 solution(s)