Merge pull request #3 from qini7/assignment3

assignmet3_133071308280_TA
13307130280_assignment5_OJ
fMerge branch 'master' of https://github.com/qini7/codebase
assignment4_merge
assignment5_master
assignment5_13307130280_OJ_0
Merge pull request #298 from qini7/assignment5

13307130280_ShizhengQin_Assignment5