Why didn't you answer any of his other questions? It's extremely hard to answer a security question without having some background knowledge. In this case, it's very important to know:

1) What is this number? If it's a password, we can simply hash it instead of encrypting it. That would eliminate the key management problem.

2) From what you are trying to protect this number? A casual glance? Something you don't want eavesdropped during transmission? Something stored locally and the user can be prompted for a key? Something stored locally, but there is no user interaction?

Your significant lack of effort is displeasing.

In reply to Re^3: How to hide a number by ikegami
in thread How to hide a number by flamel

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