package m.shin.level1; import java.util.Scanner; public class No172 { public static void main(String[] args) { Scanner s = new Scanner(System.in); int x = Math.abs(s.nextInt()) , y = Math.abs(s.nextInt()) , r = s.nextInt(); s.close(); System.out.println(Math.ceil(x + y + Math.sqrt(2)*r)); } }