Is there a way to write a large number in C++ source code with spaces to make it more readable? [duplicate]

Answer 1

When I've done similar things on platforms without C++14 (generally for microprocessors), I've represented large numbers by splitting it up with multiplication:

int i = (1000 * 1000 * 1000);

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The advantage here is that it's compliant to basically any platform that supports C89 (and probably earlier).

Generally, it's probably safe to assume the multiplication operators will fall out at compile time, but if you're using constants like this in a loop, it might be worth double-checking.