[BUG] erase_if returns an incorrect value

[sultim-t]

Describe the bug
erase_if returns current_size - old_size which is a negative value that is cast to an unsigned size_t on return.

unordered_dense/include/ankerl/unordered_dense.h

Line 1910 in fefa511

return map.size() - old_size;

To Reproduce
Steps to reproduce the behavior:

1. Call erase_if

Expected behavior
erase_if should return old_size - current_size, not current_size - old_size

System (please complete the following information):

• OS: Windows
• Compiler: MSVC
• Version 19.34.31937

Additional context
None.

[martinus]

Ha, you are of course correct, this is a bug. It seems whenever I don't have a test for something I'll do it wrong. I'll create a new release with the fix.

[martinus]

I've created release v4.0.1 with this fix. Thanks!