here are some of my codes in FB
some references/documents about multiprecision arithmetic
A Multiple-Precision Division Algorithm http://dmsmith.lmu.build/MComp1996.pdf
Simple Algorithm for Arbitrary-Precision Integer Division https://youtu.be/6bpLYxk9TUQ
Arithmetic Operations Beyond Floating Point Number Precision https://ia800403.us.archive.org/10/items/arxiv-1009.5911/1009.5911.pdf
Git repo https://github.com/nickelcarbide/arbitrary-precision-arithmetic-demo
BigInteger by Richard/Stephan https://github.com/stephanbrunker/big_integer
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