#include "integral.h"

static double f(double x) { return 4.0 / (1 + x * x); }

double integral_cpu(size_t num_intervals) {
  double dx = (1.0 / (double) num_intervals);
  double sum = 0;
  for (size_t i = 0; i < num_intervals; i++) { sum += f(i * dx) * dx; }
  return sum;
}