with open("output.txt", "r", encoding="utf-8") as file:
    lines = file.readlines()

# Преобразование: строки в верхний регистр
processed_lines = [line.upper() for line in lines]

# Запись результата в output.txt
with open("output.txt", "w", encoding="utf-8") as file:
    file.writelines(processed_lines)

print("Данные успешно обработаны и сохранены в output.txt!")