I need C++ code to Perfrom Subtraction of two Integers having more than 10 digits

For Example 123456789987654321-1234566777898978787862

https://github.com/Helios-vmg/EasyBigNum/blob/master/EasyBigNum.cpp#L218

I would like an answer to this too. I dont understand how to do it from the link.

The algorithm is fairly straightforward. It's just the subtraction algorithm children learn in school, generalized to a base that depends on the size of uintptr_t (typically base 2^32 or base 2^64).