# Re: RSA decryption exponent d (c++)

TJakobsen a écrit :
hehe sorry but i dont really understand how to use this in my program
as im only a high school student (last year though). We don't have
advanced mathematics yet and we haven't really worked with any of the
mathematics related to RSA such as modulo etc.

could someone be so kind as to go through this Extended Euclidian
algorithn using the numbers i've used in my program please?
so we can calculate d.

All those who answered you are right, you _should_ use the Euclidean
algorithm, but, since the numbers you are using are very small, you
also can find the needed inverse with an exhaustive search, i.e.,

for i := 1 to PhiN-1 do
if ((i * e) mod PhiN) = 1 then
begin
d := i;
Break;
end;

mm
.

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• Re: RSA decryption exponent d (c++)
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• Re: RSA decryption exponent d (c++)
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