Implementing K-means in C++ - c++

Question

I would be appreciate if someone could help me!
I implement kmeans algorithm in c++.
-The points that I have to split in groups are known.
-I want to make 3 clusters of them.
-But the clusters have to be instantiated randomly in the first time.
When I try it, the following message appears and I can not solve it.
Unhandled exception at 0x00007FF92B484E20 (MengeCore.dll) in menge.exe: 0xC0000005: Access violation writing location 0x0000000000000000.
The problem is in lines when I try to instantiate clusters.
Thank you in advance!!!
#include <cassert>
#include <limits>
#include <iostream>
#include <stdlib.h>
#include <time.h>
#include <list>
#include <ostream>
#include <fstream>
#include <vector>
#include <cmath>
#include <stdio.h>
using namespace std;
class Point{
private:
double x;
double y;
public:
Point::Point(double x, double y) : x(x), y(y) {}
double Point::getX() const {
return x;
}
double Point::getY() const {
return y;
}
Point::Point() {}
bool Point::operator==(const Point &rhs) const {
return x == rhs.x &&
y == rhs.y;
}
bool Point::operator!=(const Point &rhs) const {
return !(rhs == *this);
}
friend std::ostream &operator<<(std::ostream &os, const Point &point) {
os << "(" << point.x << "," << point.y << ")";
return os;
}
double getDistance(Point &p) {
return sqrt(pow(p.x - this->x, 2) + pow(p.y - this->y, 2));
}
};
class Cluster {
public:
Point centroid;
vector<int> points;
Cluster::Cluster(const Point &centroid, const vector<int> &points) : centroid(centroid), points(points) {}
Cluster::Cluster() {
}
string getPoints() {
string s = "";
for (int p : points) {
s += to_string(p + 1) + " ";
}
return s;
}
Cluster::Cluster(const Point &centroid) : centroid(centroid) {}
};
vector<Point> points{ { 9, 9 },
{ 1, 1 },
{ -1, -1 },
{ 3, 3 },
{ 10, 10 },
{ -2, -2 },
{ 7, 8 },
{ 0.2, 0 },
{-1, 0},
{ 6, 10 } };
vector<Cluster> clusters{};
int main() {
int K=2;
for (int i = 0; i < K; i++)
{
srand(time(NULL));
int RandIndex = rand() % 10; //generates a random number between 0 and 9
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
//HERE IS THE PROBLEM
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!
clusters[i].centroid = points[RandIndex];
}
return 0;
}
}

Answer 1

you should did not initialize the size for the cluster vector.
int main()
{
...
int K=2;
clusters.resize(K);
for (int i = 0; i < K; i++)
...
}