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Историческую версию 3DES можно получить на Android
Тройной алгоритм шифрования данных
Triple Data Encryption Algorithm (TDEA or Triple DEA), is a symmetric-key block cipher, which applies the DES cipher algorithm three times to each data block.
Triple DES systems are significantly more secure than single DES, but these are clearly a much slower process than encryption using single DES.
Your task is to find KEY and try to decrypt given Triple DES encrypted string.