C++ :

#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<iostream>
using namespace std;
struct P
{
    int x,y;
}a[1005];
int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    int t;
    scanf("%d",&t);
    while(t--)
    {
        int n,S;
        scanf("%d%d",&n,&S);
        for(int i=0;i<n;i++) scanf("%d%d",&a[i].x,&a[i].y);
        int sum=1;
        for(int i=0;i<n;i++)
        {
            int res=S;
            int temp=1;
            for(int j=i+1;j<n;j++)
            {
                int p=(a[i].x-a[j].x)*(a[i].x-a[j].x)+(a[i].y-a[j].y)*(a[i].y-a[j].y);
                if(res>=p)
                {
                    res-=p;
                    temp++;
                }
                else break;
            }
            sum=max(sum,temp);
        }
        printf("%d\n",sum);
    }
}