Allowed Moves: FORWARD,LEFT,RIGHT (LEFT & RIGHT at diagonals) turns are basically two phases: FORWARD, turn face then FORWARD (counts as one move with no additional cost)
There should be no additional cost for running into the rocks; as long as it takes the shorter route.
There will be no additional cost of running into a rock as long as its a shorter route. Also, if a ship tries to turn left or right from its current position; but there is a rock at that tile it will move up one tile and changes its direction.