摘要：DescriptionThere is a number of disjoint vertical line segments in the plane. We say that two segments are horizontally visible if they can be connect... 阅读全文

摘要：DescriptionYou haveNintegers,A1,A2, ... ,AN. You need to deal with two kinds of operations. One type of operation is to add some given number to each ... 阅读全文

摘要：DescriptionRailway tickets were difficult to buy around the Lunar New Year in China, so we must get up early and join a long queue…The Lunar New Year ... 阅读全文