[galaxy55]

Cryptography) A company wants to transmit data over the telephone, but is
concerned that its phones could be tapped. All of the data are transmitted as four-digi
integers. The company has asked you to write a program that encrypts the data so th
it can be transmitted more securely. Your program should read a four-digit integer an
encrypt it as follows: Replace each digit by (the sum of that digit plus 7) modulus 10.
Then, swap the first digit with the third, swap the second digit with the fourth and print
the encrypted integer. Write a separate program that inputs an encrypted four- digit
integer and decrypts it to form the original number.
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والله مااعرفت احل