// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// @dart=2.6

int fibonacci(int n) {
  if (n < 2) return n;
  return fibonacci(n - 1) + fibonacci(n - 2);
}

main() {
  for (int i = 0; i < 20; i++) {
    print(fibonacci(i));
  }
}
