Assume the coasting is an infinite straight line. Land is in one side of coasting, sea in the other.

#include
#include
#include
#include
#include
using namespace std;


struct frame
{
    double x;
    double y;
}c[1001];
struct range
{
    double l, r;
}g[1001];


bool cmp(range a, range b)
{
    return a.l }


int main()
{
    int n, d, i;
    int Case = 0;
    while(~scanf("%d%d", &n, &d))
    {
        if(n==0&&d==0)
            break;


        int sum = 1;
        for(i=0; i         {
            scanf("%lf%lf", &c[i].x, &c[i].y);
            g[i].l = c[i].x - sqrt(d*d-c[i].y*c[i].y);
            g[i].r = c[i].x + sqrt(d*d-c[i].y*c[i].y);
            if(c[i].y>d|| d<=0 || c[i].y<0) sum = -1;
        }
        sort(g, g+n, cmp);


        double m = g[0].r;
        for(i=1; i         {
            if(m < g[i].l)
            {
                sum++;
                m = g[i].r;
            }
            else if(m > g[i].r)
                m = g[i].r;
        }
        printf("Case %d: %d\n", ++Case, sum);
    }
    return 0;
}

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