/*
 * Copyright (c) 2017 - present Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */
#include <cstdarg>
#include <cstdio>

double average(int count, ...) {
  va_list ap;
  int j;
  double sum = 0;

  va_start(ap,
           count); /* Requires the last fixed parameter (to get the address) */
  for (j = 0; j < count; j++) {
    sum += va_arg(ap, int); /* Increments ap to the next argument. */
  }
  va_end(ap);

  return sum / count;
}

int main(int argc, char const* argv[]) {
  printf("%f\n", average(3, 1, 2, 3));
  return 0;
}