import os

def read_numbers_from_file(file_path):
    if not os.path.exists(file_path):
        raise FileNotFoundError(f"Файл {file_path} не найден!")

    with open(file_path, 'r') as f:
        lines = f.readlines()

    # Получаем первое и последнее число из списка строк
    first_number = int(lines[0].strip())
    last_number = int(lines[-1].strip())

    return first_number, last_number

def calculate_product(first_number, last_number):
    product = first_number * last_number
    return product

def write_result(product, output_filepath):
    with open(output_filepath, 'w') as f:
        f.write(str(product))

def main():
    input_filepath = '/var/result/data.txt'  # Исходный файл
    output_filepath = '/var/result/result.txt'  # Результирующий файл

    try:
        first_number, last_number = read_numbers_from_file(input_filepath)
        product = calculate_product(first_number, last_number)
        write_result(product, output_filepath)
        print(f"Произведение первого и последнего числа сохранено в {output_filepath}")
    except FileNotFoundError as e:
        print(e)

if __name__ == "__main__":
    main()