update assignemnt2
update assignemnt2


Former-commit-id: 15a8f37ce80e08e6220d73bf8f7a9ae98daee823 [formerly abbf6756ce5fa64c19486007c0228d33fa374984] [formerly b55ccac56fd230a3da06e3655534995b918d304a]
Former-commit-id: 605d4f3347f11937d65480db01478bba8ab94f0b
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StanfordHCI/cs247,StanfordHCI/cs247,StanfordHCI/cs247