Change `mkdir build` to `mkdir -p build` avoid failure.

[overheat]

There are 2 mkdir build will stop running when re-entry this script.

[lurch]

Duplicate of #10 and #11 ?

Just out of curiosity, why are you trying to run the script multiple times?

[overheat]

Duplicate of #10 and #11 ?

Yes
Sorry duplicate it.

Just out of curiosity, why are you trying to run the script multiple times? :(

There are some country in the world under bed networking for accessing github. I need to try few times. :(