1. A 64-bit computer^Wcalculator design

    In my public key cryptography project, this is deadly needed: non-electrical manual computer^Wcalculator, so that I can manually compute digital signature.

    Here is a figure to show the basic design of its register of 64-bit.

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    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
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    |-----------------------------------------------|
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    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    |<> <> <> <> <> <> <> <> <> <> <> <> <> <> <> <>|
    +-----------------------------------------------+
    

    It's 3-3 abacus. You may know that Japanese abacus adopts 1-4 system, while Chinese …

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