tree 15cde70521a8755cf18b13ea0c71b5382a08d8a5
parent 3952fe488ed58559bc7f473bdec07d8ebb5ead46
author Haoming Zhang <zhm1993zhm@gmail.com> 1501893014 -0700
committer Haoming Zhang <zhm1993zhm@gmail.com> 1501893014 -0700

add tests, fix bugs