随笔分类 -  树状数组

摘要：Problem DescriptionAstronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let t... 阅读全文

摘要：A potentiometer, or potmeter for short, is anelectronic device with a variable electric resistance. It has two terminals andsome kind of control mecha... 阅读全文