1 public class Point implements Comparable<Point> {
 2 
 3     public Point() {
 4         // TODO Auto-generated constructor stub
 5 
 6     }
 7 
 8     public double left;
 9     public double right;
10 
11     private void setLeft(double left) {
12         this.left = left;
13     }
14 
15     private void setRight(double right) {
16         this.right = right;
17     }
18 
19     @Override
20     public int compareTo(Point o)// 实现接口
21     {
22         if (o != null && o instanceof Point) {
23             Point p = (Point) o;
24             if (left < p.left)
25                 return -1;
26             else if (left == p.left)
27                 return 0;
28             else
29                 return 1;
30         } else
31             return -1;
32     }
33 
34     public static void main(String[] args) {
35         // TODO Auto-generated method stub
36         int n, d; // 岛屿个数和雷达侦测距离
37         Point[] poi = new Point[100]; // 存储每个岛屿
38         Scanner sc = new Scanner(System.in);
39         int num = 1; // case个数
40         int[] casenum = new int[100]; // 每个case的所需雷达数
41         n = sc.nextInt();
42         d = sc.nextInt();
43         while (n != 0 && d != 0) {
44             boolean legal = true;     //判断一个case是否合法,即能否被雷达覆盖
45             int x, y;
46             for (int i = 0; i < n; i++) {
47                 x = Integer.parseInt(sc.next());
48                 y = Integer.parseInt(sc.next());
49                 poi[i] = new Point();
50                 // System.out.println(x-Math.sqrt(d*d-y*y));
51                 // double temp1=x-Math.sqrt(d*d-y*y);
52                 poi[i].setLeft(x - Math.sqrt(d * d - y * y));
53                 poi[i].setRight(x + Math.sqrt(d * d - y * y));
54                 if (y > d)
55                     legal = false;
56             }
57             Arrays.sort(poi, 0, n);   //用到了上面重写的compareTO
58             if (!legal) {
59                 // System.out.println("Case "+num+": -1");
60                 casenum[num - 1] = -1;
61                 num++;
62             } else {
63                 double pre = poi[0].right;
64                 int radar_num = 1;
65                 for (int i = 1; i < n; i++) {
66                     if (poi[i].left > pre) {
67                         radar_num++;
68                         pre = poi[i].right;
69                     } else if (poi[i].right < pre) {
70                         pre = poi[i].right;
71                     }
72                 }
73                 // System.out.println("Case "+num+": "+radar_num);
74                 casenum[num - 1] = radar_num;
75                 num++;
76             }
77             n = sc.nextInt();
78             d = sc.nextInt();
79 
80         }
81         num--;
82         for (int i = 0; i < num; i++) {
83             int j = i + 1;
84             System.out.println("Case " + j + ": " + casenum[i]);
85         }
86 
87     }
88 
89 }