Merge pull request #2 from ds-sww/master

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first homework
first commit
hasitu
assignment1 2
assignment 1
First version of assignment3
13307130316_Liminjun_assignment3
bug fixed
commit by 13307130309
initial commit
Initial Commit
assignment1
Merge pull request #1 from ds-sww/master

ass3
Initial Commit
assignment3[initial]
Merge pull request #1 from ds-sww/master

Update
Init Commit by 12307130066
Initial TA's assignment
My solution, which seems a little naive.