XInt
A big number C++ class
XInt is a big number class that is designed to be a "drop-in" replacement for both integers and all floating point types. In theory, you could take an existing programme, replace all integer and floating point types with XInt and it should compile and run exactly as it did before but with greater precision.
There are some exceptions. Obviously, if you are relying on over/underflow behaviour, it won't work, XInt does not overflow! It will underflow but in a controlled fashion and you can specify how it behaves.
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