alright i have this problem out of my book that i bought used and goin through doin some self excersiesfor practice now this one has me stumped to ends the only thing i have so far is my dim as integer thats it but the problem reads like this:

Your application should read a four-digit integer entered by the user and encrypt it as follows: Replace each digit with the result of adding 7 to the digit and getting the remainder after dividing the new value by 10. Then swap the first digit with the third, and swap the second digit with the fourth. Then display the encrypted integer. Write a separate application that inputs an encrypted four-digit integer and decrypts it (by reversing the encryption scheme) to form the original number.

now can someone get me on the right path iam curious bout knowning how to encrypt numbers like this and have it read back but just stumps me ?? any ideas besides a dim statement where to begin ??