#include<iostream>#include<math.h>using namespace std;const int island_max=1000;int main(void){int i,j;double x[island_max],y[island_max];double num,rad;for(;;){ cin>>num>>rad;if(!(num&&rad))break;static int count=1; //记录case数目bool flag=false; for(i=0;i<num;i++){ cin>>x[i]>>y[i]; if(y[i]>rad)flag=true;}if(flag){cout<<"Case "<<count++<<": -1"<<endl;continue;}//这里由于y要随x连带排序，不能简单地使用 快排qsortdouble temp;for(i=0;i<num-1;i++)for(j=0;j<num-i-1;j++)if(x[j]>x[j+1]){temp=x[j];x[j]=x[j+1];x[j+1]=temp;temp=y[j];y[j]=y[j+1];y[j+1]=temp;}double left[island_max],righ[island_max]; //海岛圆在海岸线上的左右交点for(i=0;i<num;i++){left[i]=x[i]-sqrt(rad*rad-y[i]*y[i]);righ[i]=x[i]+sqrt(rad*rad-y[i]*y[i]);}int radar=1;for(i=0,temp=righ[0];i<num-1;i++)if(left[i+1]>temp){temp=righ[i+1];radar++;}else if(righ[i+1]<temp)temp=righ[i+1];cout<<"Case "<<count++<<": "<<radar<<endl;}return 0;}
