#include<iostream>

#include<cstdio>

#include<algorithm>

#include<cstring>

#include<cmath>

using namespace std;

const int maxn = ;

struct Node{

    double l,r;

    int x,y;

};

bool cmp(Node a,Node b)

{

    return a.r<b.r;

}

Node vc[maxn];

int main(void)

{

    int i,j,cnt,n,d,fg,x,y,pt=;

    while(scanf("%d%d",&n,&d)&&(n+d))

    {

        for(fg=,i=;i<n;i++)

        {

            scanf("%d%d",&vc[i].x,&vc[i].y);

            if(vc[i].y>d) fg=;

        }

        if(fg==)

        {

            printf("Case %d: -1\n",pt++);

            continue;

        }

        for(i=;i<n;i++)

        {

            vc[i].l=vc[i].x-sqrt(d*d*1.0-vc[i].y*vc[i].y*1.0);

            vc[i].r=vc[i].x+sqrt(d*d*1.0-vc[i].y*vc[i].y*1.0);

        }

        sort(vc,vc+n,cmp);

        for(i=,cnt=;i<n;)

        {

            double tp=vc[i].r;

            while(tp>=vc[i].l&&tp<=vc[i].r) i++;

            cnt++;

        }

        printf("Case %d: %d\n",pt++,cnt);

    }

    return ;

}