1.6.6
Fix N-Queens solution time complexity
1. Add solution 1091、1614、1619、1624、1629、1636、1704 2. ctl strings.TrimSpace question.Title
Update ctl
Merge pull request #98 from halfrost/collapsed_menu
Ctl add generate PDF
Add solution 1641
Ctl add build chapter-two
Add person data statistic