war game Q3

Vigenère多套字母密文，找出金鑰長度(< 7)、金鑰、明文

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dvq ou BrE JofsoG xtqKq iF zjs "Yqtkpsum porvhz".gnqIjp Gng qlxukt wv mnyA Hr 
CAjgFvBntf oql vsrzhurtv, trz Gntsh krtvIuqry kH umFouHhl nrn owBrsrHv BB htsds 
vz; vvlA rgtBhl vz vvh lryeFlxGoqB om pnktizr oprhkuohtuiorg. advL vgCstr ncJh 
BEogr ww vsrzhurtv sqkEErHlwA yevhury vvdB nxg svArtvwdtyE XwjmAkts fqCngFv.  
NEogruqpn MovqFqk KdA Gng tlzFz vC sCorkGk i tkpsuiy sgHkwq uh rhkvvjsuqAm c 
jlortgFh kvvjsu.