Re: [pro] Bignum Arithmetic

Hans Hübner hans.huebner@gmail.com writes:

2011/12/4 István Lakatos lakatos.isti@gmail.com:

...

The problem I ran into while trying to implement RSA in Common Lisp for my cryptography class was calculating the square root of a bignum (to demonstrate the Wiener attack on the cipher). There seems to be no bignum equivalent to floating point numbers. Are there any libraries that rectify this issue? I couldn't seem to find any.

Clozure CL implements EXPT and SQRT for bignums.

Every implementation does that. But it may overflow double floats.

There's ISQRT for integer square roots.