new
Merge remote-tracking branch 'origin/jerry'

Conflicts:
	assign2/assign2.xcodeproj/project.xcworkspace/xcuserdata/xieyangyang.xcuserdatad/UserInterfaceState.xcuserstate
Merge branch 'master' into jerry

Conflicts:
	assign2/assign2.xcodeproj/project.xcworkspace/xcuserdata/xieyangyang.xcuserdatad/UserInterfaceState.xcuserstate