Hi Minh: Good catch on line 22… I think that was some type of copy/paste error. I have fixed the article.
Your i7-2720QM CPU is only maybe 25% slower than my i7-2600K at 3.4Mhz. I was actually running the code inside a VMWARE machine but I guess that doesn’t slow things down much. Maybe you have some other things going on on your PC when you were running the code?
Chinh