<>;map{push@{-$_},-$_[--$|]for@_=glob}<>;//,map$$_=$$_?1:$',@$_ for@{-1};for$i(-2e4..(${-1}=0)){$z|=$$i*$$_&&$$i-$_&&$$_-$i&&$$i-$$_|$$i>0|$$_>0for@$i}print$z?YES:NO