OpenMP Test on Visual Studio

To use OpenMP on Visual Studio IDE, we should set in tools->options like..

Below code is to calculate pi using loop logic.
There are 5 case code.
0 case is for testing, openMP running well or not.

1 case is no treading, else 2~4 case is some different OpenMP threading case.

I am also not friendly with openMP, so I will refer this code when not remember well.
And I will add more useful technical code..

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The result image tells us, OpenMP is certainly faster than no threading.