wybooooooooo的博客

当我们想要知道从最快地从A走到B时，朴素的想法是找出任何一个点走任意步会到达的地方，但是这样太耗内存。但是实际上可以只记录走1,2,4,8,16步能到达的地方从A出发：若跳8个格子（超过B了，放弃）                  若跳4个格子（超过B了，放弃）                  若跳2个格子（没超过B，跳吧）                  若跳1个格子（没超过B，跳吧）  ...

Pog and Szh are playing games. Firstly Pog draw a tree on the paper. Here we define 1 as the root of the tree.Then Szh choose some nodes from the tree. He wants Pog helps to find the least common ance...

There are N cities in a country, and there is one and only one simple path between each pair of cities. A merchant has chosen some paths and wants to earn as much money as possible in each path. When ...