package p;

public enum Direction {NORTH, SOUTH, EAST, WEST; // note semicolon here
public Direction opposite() {
	switch (this) {
	case NORTH:
		return SOUTH;
	case SOUTH:
		return NORTH;
	case EAST:
		return WEST;
	case WEST:
		return EAST;
	default: return null;
	}
}
}