birdstorm

Alexey, a merry Berland entrant, got sick of the gray reality and he zealously wants to go to university. There are a lot of universities nowadays, so Alexey is getting lost in the diversity — he has

Our old friend Alexey has finally entered the University of City N — the Berland capital. Alexey expected his father to get him a place to live in but his father said it was high time for Alexey to pr

Problem A. Bike Roads 分段三分套三分 注意分段区间内需保证导函数单调 ac前一炮分了3*3=9个区间, WA在test 77 我最后分了最多4*4=16个区间= = Problem B. Diversion 题意是给出一个无向图, 由一颗生成树的边(type1)和一些其他边(type2)组成, 保证所有点两两双联通 现在求删去type1和type2各