Minor fixes

[RoyalXXX]

Two lines should be added to the sha2.h header file:

#include <cstdint>
#include <string>

One line should be added to the sha2.cpp:
#include <cstdint>

The program is not working correctly, you need to fix one line in the sha2.cpp file as well:

chunk[j] = std::stoull(raw.substr(j*64, 64), nullptr, 2);

I mean, stoul -> stoull