func main()
	var s: []char :: cui@input()
	var e: int :: s.findStr("OOO", -1)
	var w: int :: s.findStr("XXX", -1)
	if(e = -1)
		if(w = -1)
			do cui@print("NA")
		else
			do cui@print("West")
		end if
	elif(w = -1)
		do cui@print("East")
	else
		do cui@print(e < w ?("East", "West"))
	end if
	do cui@print("\n")
end func