博客
关于我
POJ 2312:Battle City(BFS)
阅读量:217 次
发布时间:2019-02-28

本文共 3114 字,大约阅读时间需要 10 分钟。

                                            Battle City

Time Limit: 1000MS   Memory Limit: 65536K
Total Submissions: 9885   Accepted: 3285

Description

Many of us had played the game "Battle city" in our childhood, and some people (like me) even often play it on computer now. 

What we are discussing is a simple edition of this game. Given a map that consists of empty spaces, rivers, steel walls and brick walls only. Your task is to get a bonus as soon as possible suppose that no enemies will disturb you (See the following picture). 

Your tank can't move through rivers or walls, but it can destroy brick walls by shooting. A brick wall will be turned into empty spaces when you hit it, however, if your shot hit a steel wall, there will be no damage to the wall. In each of your turns, you can choose to move to a neighboring (4 directions, not 8) empty space, or shoot in one of the four directions without a move. The shot will go ahead in that direction, until it go out of the map or hit a wall. If the shot hits a brick wall, the wall will disappear (i.e., in this turn). Well, given the description of a map, the positions of your tank and the target, how many turns will you take at least to arrive there?

Input

The input consists of several test cases. The first line of each test case contains two integers M and N (2 <= M, N <= 300). Each of the following M lines contains N uppercase letters, each of which is one of 'Y' (you), 'T' (target), 'S' (steel wall), 'B' (brick wall), 'R' (river) and 'E' (empty space). Both 'Y' and 'T' appear only once. A test case of M = N = 0 indicates the end of input, and should not be processed.

Output

For each test case, please output the turns you take at least in a separate line. If you can't arrive at the target, output "-1" instead.

Sample Input

3 4YBEBEERESSTE0 0

Sample Output

8

题意

n*m的矩阵,Y代表起点,T代表终点,R不能通过,走E需要一步,B需要两步。求从起点到终点的最短距离。如果不能到达,输出-1

AC代码

#include 
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#define ll long long#define ms(a) memset(a,0,sizeof(a))#define pi acos(-1.0)#define INF 0x3f3f3f3fconst double E=exp(1);const int maxn=1e3+10;char ch[maxn][maxn];using namespace std;int place[5][2]={1,0,-1,0,0,1,0,-1};int vis[maxn][maxn];int n,m;struct node{ int x,y,dis;}; bool operator < (const node a,const node b){ return a.dis>b.dis;}void bfs(int a,int b,int c,int d){ ms(vis); vis[a][b]=1; priority_queue
que; node start,end; start.x=a; start.y=b; start.dis=0; que.push(start); int ans=-1; while(!que.empty()) { start=que.top(); que.pop(); if(start.x==c&&start.y==d) { ans=start.dis; break; } for(int i=0;i<4;i++) { end.x=start.x+place[i][0]; end.y=start.y+place[i][1]; if(ch[end.x][end.y]=='R'||ch[end.x][end.y]=='S') continue; if(end.x<0||end.x>=n||end.y<0||end.y>=m) continue; if(vis[end.x][end.y]) continue; if(ch[end.x][end.y]=='E'||ch[end.x][end.y]=='T') end.dis=start.dis+1; if(ch[end.x][end.y]=='B') end.dis=start.dis+2; que.push(end); vis[end.x][end.y]++; } } cout<
<
>n>>m) { if(n==0&&m==0) break; ms(vis); ms(ch); int x1,x2,y1,y2; for(int i=0;i
>ch[i]; for(int i=0;i

 

转载地址:http://dcbp.baihongyu.com/

你可能感兴趣的文章
Mysql学习总结(45)——Mysql视图和事务
查看>>
Mysql学习总结(46)——8种常被忽视的SQL错误用法
查看>>
war包放到webapps下,启动tomcat,tomcat正常,却无法加载项目
查看>>
Mysql学习总结(48)——MySql的日志与备份还原
查看>>
Mysql学习总结(49)——从开发规范、选型、拆分到减压
查看>>
Mysql学习总结(4)——MySql基础知识、存储引擎与常用数据类型
查看>>
Mysql学习总结(50)——Oracle,mysql和SQL Server的区别
查看>>
Mysql学习总结(51)——Linux主机Mysql数据库自动备份
查看>>
Mysql学习总结(52)——最全面的MySQL 索引详解
查看>>
Mysql学习总结(53)——使用MySql开发的Java开发者规范
查看>>
Mysql学习总结(54)——MySQL 集群常用的几种高可用架构方案
查看>>
Mysql学习总结(55)——MySQL 语句大全再温习
查看>>
Mysql学习总结(56)——MySQL用户管理和权限设置
查看>>
Mysql学习总结(57)——MySQL查询当天、本周、本月、上周、本周、上月、距离当前现在6个月数据
查看>>
Mysql学习总结(58)——深入理解Mysql的四种隔离级别
查看>>
Mysql学习总结(59)——数据库分库分表策略总结
查看>>
Mysql学习总结(5)——MySql常用函数大全讲解
查看>>
Mysql学习总结(60)——并发量大、数据量大的互联网业务数据库设计规范总结
查看>>
Mysql学习总结(61)——MySQL优化之DBA级优化整理汇总
查看>>
Mysql学习总结(62)——MySQL连接com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link问题
查看>>