### Question:
App { public static void main(final String[] args) { final var nums = new int[]{1, 2, 3, 4, 5}; final var oldSystem = new OldArithmetic(new OldSource()); oldSystem.sum(nums); oldSystem.mul(nums); final var halfSystem = new HalfArithmetic(new HalfSource(), new OldSource()); halfSystem.sum(nums); halfSystem.mul(nums); halfSystem.ifHasZero(nums); final var newSystem = new NewArithmetic(new NewSource()); newSystem.sum(nums); newSystem.mul(nums); newSystem.ifHasZero(nums); }  static void main(final String[] args);  }### Answer:
@Test void shouldExecuteWithoutException() { assertDoesNotThrow(() -> App.main(new String[]{})); }