POJ 3278 Catch That Cow (BFS + 剪枝)
Farmer John has been informed of the location of a fugitive cow and wants to catch her immediately. He starts at a point N (0 ≤ N ≤ 100,000) on a number line and the cow is at a point K (0 ≤ K ≤ 100,000) on the same number line. Farmer John has two modes of transportation: walking and teleporting.
* Walking: FJ can move from any point X to the points X - 1 or X + 1 in a single minute
* Teleporting: FJ can move from any point X to the point 2 × X in a single minute.
If the cow, unaware of its pursuit, does not move at all, how long does it take for Farmer John to retrieve it?
Line 1: Two space-separated integers: N and K
Line 1: The least amount of time, in minutes, it takes for Farmer John to catch the fugitive cow.
The fastest way for Farmer John to reach the fugitive cow is to move along the following path: 5-10-9-18-17, which takes 4 minutes.
这个地球真太小了，在地铁上看小米的面经写到了一个算法题，心想挺有意思的，回去写写。回家继续写 kuangbin 带你飞 的题目，结果发现第三道刚好是面经中看到的。太小了太小了。简单题目。哈哈哈，看到 Teleporting 的时候第一反应是 TP。