超市卖的都是45厘米或50厘米宽的，淘宝搜到有（http://item.taobao.com/auction/item_detail--.jhtml?taomi=8aR2LQR6GJA6mBG%2FpudO%2BMKbGHaHwNpJc0kkO8gJqR7xR0om9S1yZ1pzHFSPbnjbfIXW95Mx22NJ22m6Nk29FOTP84MteMBMzqiNT2Mxbq%2B2eGSAinHalGcGybSKScKaWaWXINPiRdafd8KlIXBCmdrbhfhsb5qyLzRHEhYiqH58FjmGRvVScY7nVJOO1RZAQ9UpFM%2F%2BTBl1bl7RBzlohlDNvQnDxAIDDqv8nYQOEfQZ0oayUIDwWghrx39o&ref=http%3A%2F%2Fsearch8.taobao.com%2Fbrowse%2F0%2Fn-66---------------g%2Cnvwv6mjxgaztonzrgrptaxzq---------------------------------------g%2Czgz3pivv4yqmf2n5vm----------------40--commend-0-all-0.htm%3Fat_topsearch%3D1%26alhlog%3Ds8-top-search%26f%3Dc&ali_trackid=2:mm_17037714_0_0:109292537_2_968642176），可惜邮费好贵，经常扫街的达人，告诉个地，就像这样的，可以裁成任意长度
