#include <chrono>
#include <iostream>
#include <math.h>

// function to add the elements of two arrays
void add(int n, float *x, float *y) {
  for (int i = 0; i < n; i++)
    y[i] = x[i] + y[i];
}

int main(void) {
  int N = 1 << 29;

  float *x = new float[N];
  float *y = new float[N];

  // initialize x and y arrays on the host
  for (int i = 0; i < N; i++) {
    x[i] = 1.0f;
    y[i] = 2.0f;
  }

  // Start chrono timer
  auto start_time = std::chrono::high_resolution_clock::now();

  // Run kernel on N << 29 elements on the CPU
  add(N, x, y);

  // Timer ends after the add function call
  auto end_time = std::chrono::high_resolution_clock::now();

  // Calculate elapsed time
  std::chrono::duration<double> elapsed = end_time - start_time;
  std::cout << "Elapsed time: " << elapsed.count() << " seconds" << std::endl;

  // Check for errors (all values should be 3.0f)
  float maxError = 0.0f;
  for (int i = 0; i < N; i++)
    maxError = fmax(maxError, fabs(y[i] - 3.0f));
  std::cout << "Max error: " << maxError << std::endl;

  // Free memory
  delete[] x;
  delete[] y;

  return 0;
}