func main()
	var X: int :: cui@input().toInt(&)
	var Y: int :: cui@input().toInt(&)
	var L: int :: cui@input().toInt(&)
	
	var ans: int
	if(Y < 0)
		do ans :+ 2
	elif(X <> 0)
		do ans :+ 1
	end if
	do ans :+ (X.abs() + L - 1) / L
	do ans :+ (Y.abs() + L - 1) / L
	do cui@print("\{ans}\n")
end func