CodeForces
来源:互联网 发布:博达软件 编辑:程序博客网 时间:2024/06/05 09:46
You play a computer game. Your character stands on some level of a multilevel ice cave. In order to move on forward, you need to descend one level lower and the only way to do this is to fall through the ice.
The level of the cave where you are is a rectangular square grid of n rows and mcolumns. Each cell consists either from intact or from cracked ice. From each cell you can move to cells that are side-adjacent with yours (due to some limitations of the game engine you cannot make jumps on the same place, i.e. jump from a cell to itself). If you move to the cell with cracked ice, then your character falls down through it and if you move to the cell with intact ice, then the ice on this cell becomes cracked.
Let's number the rows with integers from 1 to n from top to bottom and the columns with integers from 1 to m from left to right. Let's denote a cell on the intersection of the r-th row and the c-th column as (r, c).
You are staying in the cell (r1, c1) and this cell is cracked because you've just fallen here from a higher level. You need to fall down through the cell (r2, c2)since the exit to the next level is there. Can you do this?
The first line contains two integers, n and m (1 ≤ n, m ≤ 500) — the number of rows and columns in the cave description.
Each of the next n lines describes the initial state of the level of the cave, each line consists of m characters "." (that is, intact ice) and "X" (cracked ice).
The next line contains two integers, r1 and c1 (1 ≤ r1 ≤ n, 1 ≤ c1 ≤ m) — your initial coordinates. It is guaranteed that the description of the cave contains character 'X' in cell (r1, c1), that is, the ice on the starting cell is initially cracked.
The next line contains two integers r2 and c2 (1 ≤ r2 ≤ n, 1 ≤ c2 ≤ m) — the coordinates of the cell through which you need to fall. The final cell may coincide with the starting one.
If you can reach the destination, print 'YES', otherwise print 'NO'.
4 6X...XX...XX..X..X.......1 62 2
YES
5 4.X.....XX.X......XX.5 31 1
NO
4 7..X.XX..XX..X.X...X..X......2 21 6
YES
In the first sample test one possible path is:
After the first visit of cell (2, 2) the ice on it cracks and when you step there for the second time, your character falls through the ice as intended.
数据太大,只有bfs。
代码如下:
#include<stdio.h>#include<string.h>#include<queue>#include<algorithm>using namespace std;int n,m;char mapp[550][550];int a,b,c,d,f;int dir[4][2]= {1,0,-1,0,0,1,0,-1};struct note{ int x,y;};int bfs(int x,int y){ queue<note>Q; note p,q; p.x=x; p.y=y; Q.push(p); while(!Q.empty()) { p=Q.front(); Q.pop(); for(int i=0; i<4; i++) { q.x=p.x+dir[i][0]; q.y=p.y+dir[i][1]; if(q.x<0||q.y<0||q.x>=n||q.y>=m)continue; if(q.x==c&&q.y==d) { if(mapp[q.x][q.y]=='.') mapp[q.x][q.y]='X'; else return 1; Q.push(q); } else if(mapp[q.x][q.y]=='.') { mapp[q.x][q.y]='X'; Q.push(q); } } } return 0;}int main(){ while(~scanf("%d%d",&n,&m)) { for(int i=0; i<n; i++) scanf("%s",mapp[i]); scanf("%d%d",&a,&b); scanf("%d%d",&c,&d); a--; b--; c--; d--; if(bfs(a,b))printf("YES\n"); else printf("NO\n"); } return 0;}
- codeforces~~~
- Codeforces
- codeforces
- Codeforces
- codeforces
- codeforces
- Codeforces
- Codeforces
- CodeForces
- CodeForces
- CodeForces
- CodeForces
- CodeForces
- Codeforces
- Codeforces
- Codeforces
- Codeforces
- Codeforces
- C#指定图片添加文字
- springboot-加载自定义的properties文件
- 主从复制、读写分离水平拆分及库表散列
- Java编辑pdf
- oracle数据库用户管理操作(DCL)
- CodeForces
- 常见的简单笔试题却又要小心的题
- Unity2D游戏入门教程(一)宝石迷阵(1)创建项目
- hdu 1018
- 打印当前时间。
- 【C#】身份证识别(三):身份证信息识别
- yolo_v2训练自己的数据出现Obj: 0.000000, No Obj: 0.000000
- 通过ansible批量设置随机密码
- vmware linux和windows共享文件失效问题解决