Ошибка рисования с помощью SFML

#include <iostream>
#include <conio.h>
#include "helpfunctions.h"
#include <SFML/Graphics.hpp>
#include <vector>
#include <cmath>
 
using namespace std;
 
void trees()
{
    const int WIDTH = 1920;
    const int HEIGHT = 1080;
    const float RADIUS = 5.f;
    const float LINE_THICKNESS = 2.f;
 
    sf::RenderWindow window(sf::VideoMode(WIDTH, HEIGHT), "Forest Fence");
    
    int n;
    cin >> n;
    vector<sf::Vector2f> trees(n);
    for (int i = 0; i < n; ++i)
        cin >> trees[i].x >> trees[i].y;
 
    int i1 = 0, i2 = 1, i3 = 2;
    for (int i = 0; i < n; ++i)
        for (int j = i + 1; j < n; ++j)
            for (int k = j + 1; k < n; ++k)
            {
                float a = sqrt(pow(trees[j].x - trees[i].x, 2) + pow(trees[j].y - trees[i].y, 2));
                float b = sqrt(pow(trees[k].x - trees[i].x, 2) + pow(trees[k].y - trees[i].y, 2));
                float c = sqrt(pow(trees[k].x - trees[j].x, 2) + pow(trees[k].y - trees[j].y, 2));
                float p = (a + b + c) / 2.f;
                float r = a * b * c / (4.f * sqrt(p * (p - a) * (p - b) * (p - c)));
                if (i1 == i && i2 == j && i3 == k) continue;
                float R = sqrt(pow(trees[i].x - trees[j].x, 2) + pow(trees[i].y - trees[j].y, 2));
                if (r < R) { i1 = i; i2 = j; i3 = k; }
            }
 
    vector<sf::VertexArray> fences(n);
    for (int i = 0; i < n; ++i)
    {
        if (i == i1 || i == i2 || i == i3) continue;
        float d1 = sqrt(pow(trees[i].x - trees[i1].x, 2) + pow(trees[i].y - trees[i1].y, 2));
        float d2 = sqrt(pow(trees[i].x - trees[i2].x, 2) + pow(trees[i].y - trees[i2].y, 2));
        float d3 = sqrt(pow(trees[i].x - trees[i3].x, 2) + pow(trees[i].y - trees[i3].y, 2));
        int i_min = min({ d1, d2, d3 });
        if (i_min == d1) fences[i].append(sf::Vertex(trees[i], sf::Color::White));
        else if (i_min == d2) fences[i].append(sf::Vertex(trees[i], sf::Color::White));
        else fences[i].append(sf::Vertex(trees[i], sf::Color::White));
        if (i_min == d1) fences[i].append(sf::Vertex(trees[i1], sf::Color::White));
        else if (i_min == d2) fences[i].append(sf::Vertex(trees[i2], sf::Color::White));
        else fences[i].append(sf::Vertex(trees[i3], sf::Color::White));
    }
 
    float length = 0.f;
    for (int i = 0; i < n; ++i)
    {
        if (i == i1 || i == i2 || i == i3) continue;
        float d = sqrt(pow(trees[i].x - fences[i][0].position.x, 2) + pow(trees[i].y - fences[i][0].position.y, 2));
        length += d;
    }
 
    while (window.isOpen())
    {
        sf::Event event;
        while (window.pollEvent(event))
        {
            if (event.type == sf::Event::Closed) window.close();
        }
 
        window.clear(sf::Color::Black);
 
        // Отображение деревьев
        for (int i = 0; i < n; ++i)
        {
            sf::CircleShape tree(RADIUS);
            tree.setFillColor(sf::Color::Green);
            tree.setOrigin(RADIUS, RADIUS);
            tree.setPosition(trees[i]);
            window.draw(tree);
        }
 
        // Отображение заборов
        for (int i = 0; i < n; ++i)
        {
            window.draw(fences[i], LINE_THICKNESS, sf::Lines);
        }
 
        window.display();
    }
}
 
int main()
{
    trees();
    return 0;
}