贡献了无数的Presentation Error，调的心都要碎了
一定要注意输出格式啊。。。。。。。

#include<iostream>
#include<Cstdio>
#include <algorithm> 
#include<Cmath>
#include<Cstring>

using namespace std;

struct Node
{
	double a1, a2;
};

Node pos[1001];
bool used[1001];


void ShellSort(Node array[],int length)
{
	int d = length/2;   //设置希尔排序的增量
	int i ;
	int j;
	Node temp;
	while(d>=1)    
    {
		for(i=d;i<length;i++)    
		{    
			temp=array[i];
			j=i-d;
			while(j>=0 && array[j].a2> temp.a2)    
			{    
				array[j+d]=array[j];    
				j=j-d;    
			}    
			array[j+d] = temp;    
		}
			   
	   d= d/2;    //缩小增量    
	}
}

int Check(Node array[],int length)
{
	int size = 0, index;
	double min;
	memset(used, false, length);
	
	while (1) 
	{
	   for(int i = 0; i < length; ++i)
	   {
		   if(!used[i])
		   {
			   min = array[i].a2 + 0.000001;
			   index = i;
			   break;
		   }
	   }
		//cout << "Min is"<<min << endl;
	   bool flag = true;
	   for(int i = 0; i < length; ++i)
	   {
		   if(!used[i] && array[i].a1 < min)
		   {
			   used[i] = true;
		   }
		   flag &= used[i];
		   //cout << used[i] << endl;
	   } 
	
		size++;
	   if(flag)
		   return size;
		   
	}
	return -1;
}


int main()
{
	int n, i, ans, size, num = 1, count;
	double x, y, d, temp;
	bool flag;
	while (1)
	{
		cin >> n >> d;
		if(n == 0 && d == 0)
			break;
		count = 0;
		flag = true;
		for(i = 0; i < n; ++i)
		{
			cin >> x >> y;
			if(d > 0 && d*d-y*y >= -0.00000001)
			{
		        pos[count].a1 = x - sqrt(d*d-y*y);
				pos[count].a2 = x + sqrt(d*d-y*y);
				count ++;
			}
			else
			{
				flag = false;
			}
		}
		
		
		if(flag)
		{
		    ShellSort(pos, count);
			
//			for(int i = 0; i < count; ++i)
//				cout << pos[i].a1 << " " << pos[i].a2 << endl;
			
		    size = Check(pos, count);

			cout << "Case "<<num << ": " << size << endl;
			num ++;
			
		}
		else
		{
			cout << "Case "<<num << ": " << -1 << endl;
			num ++;
		}

		
	}

   return 0;
}