思路没有错啊 为啥我这个写法就10分

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>

using namespace std;

struct Point{
    double x, y;

    Point() {}
    Point(double _x, double _y){
        x = _x;
        y = _y;


    }


    double len(){
        return sqrt(1.0 * x * x + 1.0 * y * y);

    }
    //判断点是否重合
    bool operator == (const Point& w) const{
        return x == w.x && y == w.y;
    }

    Point operator - (const Point& w) const{
        return Point(x - w.x, y - w.y);
    }

    Point operator + (const Point& w) const{
        return Point(x + w.x, y + w.y);

    }

    double operator * (const Point&w) const{//点积
        return x * w.x + y * w.y;

    }

    double operator ^ (const Point&w) const{//叉积
        return x * w.y - y * w.x;
    }

    void print(){//打印当前坐标或者是向量
        cout << x << ' ' << y << endl;

    }

    bool operator < (const Point&w) const{
        if (x != w.x) return x < w.x;
        else return y > w.y;

    }

};

const int N = 1010;

int n, d;
Point p[N];

int main(){
    cin >> n >> d;

    for (int i = 1; i <= n; i ++){
        cin >> p[i].x >> p[i].y;
        if (p[i].y > d) {
            cout << -1;
            return 0;

        }
    }



    sort(p + 1, p + 1 + n);

    int cnt = 0, pos = -2000010;

    Point dot = {pos, 0};

    for (int i = 1; i <= n; i ++){
        Point o = p[i] - dot;
        if (o.x * o.x + o.y * o.y > d * d){
            double x = sqrt(d * d - p[i].y * p[i].y);
            dot.x = p[i].x + x;
            cnt ++;   
        }

    }

    cout << cnt << endl;

}