用c++写一个点云最小生成树

好的，我可以给你提供一个基于Prim算法的点云最小生成树的C++代码实现，如下所示：

#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>

using namespace std;

const int MAXN = 1e3 + 5;

struct Point {
    double x, y;
    Point() : x(0), y(0) {}
    Point(double x, double y) : x(x), y(y) {}
};

struct Edge {
    int u, v;
    double w;
    Edge() : u(0), v(0), w(0) {}
    Edge(int u, int v, double w) : u(u), v(v), w(w) {}
};

int n;
Point p[MAXN];
vector<Edge> e;

double dist(Point a, Point b) {
    double dx = a.x - b.x, dy = a.y - b.y;
    return sqrt(dx * dx + dy * dy);
}

void prim() {
    bool vis[MAXN] = { false };
    double d[MAXN] = { 0 };
    int pre[MAXN] = { 0 };
    for (int i = 2; i <= n; i++) {
        d[i] = dist(p[1], p[i]);
        pre[i] = 1;
    }
    vis[1] = true;
    for (int i = 1; i < n; i++) {
        int u = 0;
        double min_d = 1e9;
        for (int j = 2; j <= n; j++) {
            if (!vis[j] && d[j] < min_d) {
                u = j;
                min_d = d[j];
            }
        }
        if (u == 0) break;
        vis[u] = true;
        e.push_back(Edge(pre[u], u, min_d));
        for (int j = 2; j <= n; j++) {
            double w = dist(p[u], p[j]);
            if (!vis[j] && w < d[j]) {
                d[j] = w;
                pre[j] = u;
            }
        }
    }
}

int main() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> p[i].x >> p[i].y;
    }
    prim();
    double ans = 0;
    for (int i = 0; i < e.size(); i++) {
        ans += e[i].w;
    }
    cout << ans << endl;
    return 0;
}

该代码实现了一个基于Prim算法的点云最小生成树，输入格式为点云的个数n和n个点的坐标(x, y)，输出为点云的最小生成树长度。