Extra line is drawn when i draw cobweb plot

[NikoMolecule]

Hello, so when I rendered my cobweb plot extra line was drawn near to the fixed point aka the point with most red lines. extra line is shown down in this picture, so can anyone help me to fix it?

#include <glad/glad.h>
#include <GLFW/glfw3.h>

#include <iostream>
#include <vector>

using namespace std;

unsigned int createShader(unsigned int shadertype, const char* shaderSource) {
  unsigned int shader;
  shader = glCreateShader(shadertype);
  glShaderSource(shader, 1, &shaderSource, NULL);
  glCompileShader(shader);

  int status;
  char info[512];
  glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
  if (!status) {
    glGetShaderInfoLog(shader, 512, NULL, info);
    cout << "FAILED TO COMPILE!\n" << info << '\n';
    glDeleteShader(shader);
  }

  return shader;
}

unsigned int createShaderProgram(const char* VshaderSrc, const char* FshaderSrc) {
  unsigned int vertexShader = createShader(GL_VERTEX_SHADER, VshaderSrc);
  unsigned int fragmentShader = createShader(GL_FRAGMENT_SHADER, FshaderSrc);

  unsigned int shaderProgram;
  shaderProgram = glCreateProgram();

  glAttachShader(shaderProgram, vertexShader);
  glAttachShader(shaderProgram, fragmentShader);
  glLinkProgram(shaderProgram);

  int status;
  char info[512];
  glGetProgramiv(shaderProgram, GL_LINK_STATUS, &status);
  if (!status) {
    glGetProgramInfoLog(shaderProgram, 512, NULL, info);
    cout << "FAILED TO LINK PROGRAM\n" << info << '\n';
  }

  return shaderProgram;
}

void framebuffer_size_callback(GLFWwindow* window, int width, int height) {
  glViewport(0, 0, width, height);
}

void closeWindow(GLFWwindow* window) {
  if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS) {
    glfwSetWindowShouldClose(window, true);
  }
}

void cobwebDiagmramForLogistics(float x0, float miu, float* ptr) {
  float y = miu * x0 * (1.0f - x0);

  *(ptr) = x0 * 2 - 1;
  *(ptr + 1) = -1.0f;
  *(ptr + 2) = 0.0f;

  *(ptr + 3) = x0 * 2 - 1;
  *(ptr + 4) = y * 2 - 1;
  *(ptr + 5) = 0.0f;

  for (int i = 1; i < 100; i++) {
    *(ptr + i * 6) = y * 2 - 1;
    *(ptr + i * 6 + 1) = y * 2 - 1;
    *(ptr + i * 6 + 2) = 0.0f;

    *(ptr + i * 6 + 3) = y * 2 - 1;
    y *= (1.0f - y) * miu;

    *(ptr + i * 6 + 4) = y * 2 - 1;
    *(ptr + i * 6 + 5) = 0.0f;
  }
}

int main() {
  float CobwebPlot[600];
  cobwebDiagmramForLogistics(0.085f, 2.8f, &CobwebPlot[0]);
  vector<unsigned int> v;
  v.push_back(0);
  for (int i = 1; i < 598; i += 2) {
      v.push_back(i);
      v.push_back(i);
      v.push_back(i + 1);
      v.push_back(i + 1);
  }
  v.push_back(599);
  int size = v.size();
  unsigned int positions[1198];
  for (int i = 0; i < v.size(); i++) {
      positions[i] = v[i];

      cout << positions[i] << ' ';
  }

  glfwInit();
  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 4);
  glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

  GLFWwindow* window = glfwCreateWindow(800, 600, "Cobweb_Diagram", NULL, NULL);

  if (window == NULL) {
    cout << "Failed to create GLFW window" << endl;
    glfwTerminate();
    return -1;
  }

  glfwMakeContextCurrent(window);
  if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
      cout << "Failed to initialize GLAD" << endl;
      return -1;
  }

  unsigned int cobwebBuffer;
  unsigned int bufferArray;
  unsigned int elementArray;
  glGenVertexArrays(1, &bufferArray);
  glGenBuffers(1, &cobwebBuffer);
  glGenBuffers(1, &elementArray);

  glBindVertexArray(bufferArray);

  glBindBuffer(GL_ARRAY_BUFFER, cobwebBuffer);
  glBufferData(GL_ARRAY_BUFFER, sizeof(CobwebPlot), CobwebPlot, GL_STATIC_DRAW);

  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementArray);
  glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(positions), positions,
               GL_STATIC_DRAW);

  glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
  glEnableVertexAttribArray(0);

  const char* vertexShaderSource =
      "#version 330 core\n"
      "layout (location = 0) in vec3 aPos;\n"
      "void main()\n"
      "{\n"
      "   gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);\n"
      "}\0";

  const char* fragmentShaderSource = R"(
      #version 330 core
      out vec4 lineColor;
      void main()
      {
          lineColor = vec4(1.0f, 0.1f, 0.2f, 1.0f);
      }
)";

  unsigned int shaderProgram =
      createShaderProgram(vertexShaderSource, fragmentShaderSource);

  glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);

  while (!glfwWindowShouldClose(window)) {
    closeWindow(window);

    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    glBindVertexArray(bufferArray);
    glUseProgram(shaderProgram);
    glDrawElements(GL_LINES, 1198, GL_UNSIGNED_INT, 0);
    glBindVertexArray(0);

    glfwSwapBuffers(window);
    glfwPollEvents();
  }

  glfwTerminate();
  return 0;
}

[GClements]

You’re drawing 600 vertices but you only have the data for 200. Given that the endpoint appears to be in the centre of the screen, I’d assume that the extra vertices are being read as (0,0,0).