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Reverse a RoadTime Limit 1000msMemory Limit 65536Kdescription Peter resides in the city of Nanuh, and goes to his working place in this city every weekday.He has been totally annoyed with the road traffic of this city. All the roads in this city are one-way, so he has to drive a longer way than he . 阅读全文
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TripTime Limit 1000msMemory Limit 65536Kdescription Xiao wang has a new car, so he wants to have a trip from his home to hefei, however, there is no road from his house directly to Hefei, so he has to go through a number of cities to get to hefei, his car takes one unit of time driving a unit dista. 阅读全文
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Magic TreeTime Limit 1000msMemory Limit 65536Kdescription Every acmer dream for gold medal. Fotunately,there are two magic trees (which are conveniently numbered 1 and 2) in our campus, each full of gold medal. The trees are very high, so we can not touch the gold medal when they are in the tree bu. 阅读全文
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GridsTime Limit 1000msMemory Limit 65536KdescriptionOn an 1 × 1 grid,partition the length and width into 50 parts,forming 2500 unit grids with the same size.Now,given n circles with equal radius R on the grid.Find the total number of unit grids which are not covered by any of a circle. A unit g 阅读全文