2014.6.14模拟赛【bzoj1646】[Usaco2007 Open]Catch That Cow 抓住那只牛
2014-06-14 21:39
459 查看
Description
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 modesof 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?
农夫约翰被通知,他的一只奶牛逃逸了!所以他决定,马上幽发,尽快把那只奶牛抓回来.
他们都站在数轴上.约翰在N(O≤N≤100000)处,奶牛在K(O≤K≤100000)处.约翰有
两种办法移动,步行和瞬移:步行每秒种可以让约翰从z处走到x+l或x-l处;而瞬移则可让他在1秒内从x处消失,在2x处出现.然而那只逃逸的奶牛,悲剧地没有发现自己的处境多么糟糕,正站在那儿一动不动.
那么,约翰需要多少时间抓住那只牛呢?
Input
* Line 1: Two space-separated integers: N and K仅有两个整数N和K.
Output
* Line 1: The least amount of time, in minutes, it takes for Farmer John to catch the fugitive cow.最短的时间.
Sample Input
5 17Farmer John starts at point 5 and the fugitive cow is at point 17.
Sample Output
4OUTPUT DETAILS:
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.
好裸的bfs……n的规模才10w
原来还想的是二进制dp,结果发现我在没事找事……
#include<cstdio> #include<iostream> #include<cstring> using namespace std; int n,m,head,tail=1; int dist[500001]; int q[500001]; inline bool mark(int x) { return !(x<0||x>max(2*m+1,n+1)); } int main() { freopen("catchcow.in","r",stdin); freopen("catchcow.out","w",stdout); scanf("%d%d",&n,&m); memset(dist,-1,sizeof(dist)); q[1]=n;dist =0; while (head<tail) { head++; int now=q[head]-1; if(mark(now)&&dist[now]==-1) { q[++tail]=now; dist[now]=dist[q[head]]+1; } now=q[head]+1; if(mark(now)&&dist[now]==-1) { q[++tail]=now; dist[now]=dist[q[head]]+1; } now=q[head]*2; if(mark(now)&&dist[now]==-1) { q[++tail]=now; dist[now]=dist[q[head]]+1; } if(dist[m]!=-1) {printf("%d",dist[m]);return 0;} } }
相关文章推荐
- 2014.6.14模拟赛【bzoj1646】[Usaco2007 Open]Catch That Cow 抓住那只牛
- bzoj'1646: [Usaco2007 Open]Catch That Cow 抓住那只牛
- [BZOJ1646] [Usaco2007 Open]Catch That Cow 抓住那只牛
- BZOJ 1646:[Usaco2007 Open]Catch That Cow 抓住那只牛
- [BZOJ] 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛
- BZOJ1646: [Usaco2007 Open]Catch That Cow 抓住那只牛
- BZOJ1646: [Usaco2007 Open]Catch That Cow 抓住那只牛
- BZOJ 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛
- bzoj 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛 bfs
- 【BZOJ】1646: [Usaco2007 Open]Catch That Cow 抓住那只牛(bfs)
- BZOJ 1646[Usaco2007 Open]Catch That Cow 抓住那只牛 双向bfs版
- poj 3278 && bzoj 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛(BFS)
- bzoj1646 [Usaco2007 Open]Catch That Cow 抓住那只牛
- 【BZOJ 1646】 [Usaco2007 Open]Catch That Cow 抓住那只牛
- BZOJ 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛( BFS )
- bzoj 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛【bfs】
- BZOJ 1646: [Usaco2007 Open]Catch That Cow 抓住那只牛
- [BZOJ 1647][USACO 2007 Open] Fliptile 翻格子游戏
- bzoj 1711: [Usaco2007 Open]Dining吃饭 网络流
- BZOJ2679 : [Usaco2012 Open]Balanced Cow Subsets