# Nightmare
**Time Limit: 2000/1000 MS (Java/Others)????Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 9120????Accepted Submission(s): 4389**
Problem Description
Ignatius had a nightmare last night. He found himself in a labyrinth with a time bomb on him. The labyrinth has an exit, Ignatius should get out of the labyrinth before the bomb explodes. The initial exploding time of the bomb is set to 6 minutes. To prevent the bomb from exploding by shake, Ignatius had to move slowly, that is to move from one area to the nearest area(that is, if Ignatius stands on (x,y) now, he could only on (x+1,y), (x-1,y), (x,y+1), or (x,y-1) in the next minute) takes him 1 minute. Some area in the labyrinth contains a Bomb-Reset-Equipment. They could reset the exploding time to 6 minutes.
Given the layout of the labyrinth and Ignatius' start position, please tell Ignatius whether he could get out of the labyrinth, if he could, output the minimum time that he has to use to find the exit of the labyrinth, else output -1.
Here are some rules:
1\. We can assume the labyrinth is a 2 array.
2\. Each minute, Ignatius could only get to one of the nearest area, and he should not walk out of the border, of course he could not walk on a wall, too.
3\. If Ignatius get to the exit when the exploding time turns to 0, he can't get out of the labyrinth.
4\. If Ignatius get to the area which contains Bomb-Rest-Equipment when the exploding time turns to 0, he can't use the equipment to reset the bomb.
5\. A Bomb-Reset-Equipment can be used as many times as you wish, if it is needed, Ignatius can get to any areas in the labyrinth as many times as you wish.
6\. The time to reset the exploding time can be ignore, in other words, if Ignatius get to an area which contain Bomb-Rest-Equipment, and the exploding time is larger than 0, the exploding time would be reset to 6.
Input
The input contains several test cases. The first line of the input is a single integer T which is the number of test cases. T test cases follow.
Each test case starts with two integers N and M(1<=N,Mm=8) which indicate the size of the labyrinth. Then N lines follow, each line contains M integers. The array indicates the layout of the labyrinth.
There are five integers which indicate the different type of area in the labyrinth:
0: The area is a wall, Ignatius should not walk on it.
1: The area contains nothing, Ignatius can walk on it.
2: Ignatius' start position, Ignatius starts his escape from this position.
3: The exit of the labyrinth, Ignatius' target position.
4: The area contains a Bomb-Reset-Equipment, Ignatius can delay the exploding time by walking to these areas.
Output
For each test case, if Ignatius can get out of the labyrinth, you should output the minimum time he needs, else you should just output -1.
Sample Input
~~~
3
3 3
2 1 1
1 1 0
1 1 3
4 8
2 1 1 0 1 1 1 0
1 0 4 1 1 0 4 1
1 0 0 0 0 0 0 1
1 1 1 4 1 1 1 3
5 8
1 2 1 1 1 1 1 4
1 0 0 0 1 0 0 1
1 4 1 0 1 1 0 1
1 0 0 0 0 3 0 1
1 1 4 1 1 1 1 1
~~~
Sample Output
~~~
4
-1
13
~~~
代碼:
~~~
#include<cstdio>
#include<cstring>
#include<queue>
using namespace std;
struct node
{
int x,y;
int t;
int step;
node(int a,int b,int c,int d):x(a),y(b),t(c),step(d) {}
void Set(int a,int b,int c,int d)
{
x=a;
y=b;
t=c;
step=d;
}
};
int n,m;
int xs,ys,xe,ye;
int mat[10][10];
int vis[10][10];
int dir[4][2]= {-1,0,1,0,0,-1,0,1}; //up down left right
void bfs()
{
memset(vis,0,sizeof(vis));
queue<node> Q;
node first=node(xs,ys,6,0);
if(first.x==xe&&first.y==ye&&first.t>0)
{
printf("%d\n",first.step);
return;
}
Q.push(first);
vis[first.x][first.y]=first.t;
while(!Q.empty())
{
//printf("----------------\n");
first=Q.front();
Q.pop();
node next=node(0,0,0,0);
for(int i=0; i<4; i++)
{
int tx=first.x+dir[i][0];
int ty=first.y+dir[i][1];
if(tx>=n||tx<0||ty>=m||ty<0)
continue;
if(mat[tx][ty]==0)
continue;
if(vis[tx][ty]+1>=vis[first.x][first.y])
continue;
next.Set(tx,ty,first.t-1,first.step+1);
if(mat[tx][ty]==4)
next.t=6;
vis[next.x][next.y]=next.t;
//printf("%d %d %d %d\n",next.x,next.y,next.t,next.step);
if(next.x==xe&&next.y==ye&&next.t>0)
{
printf("%d\n",next.step);
return;
}
Q.push(next);
}
}
printf("-1\n");
}
int main()
{
int t;
scanf("%d",&t);
//printf("%d\n",t);
while(t--)
{
scanf("%d%d",&n,&m);
for(int i=0; i<n; i++)
{
for(int j=0; j<m; j++)
{
scanf("%d",&mat[i][j]);
if(mat[i][j]==2)
{
xs=i;
ys=j;
}
if(mat[i][j]==3)
{
xe=i;
ye=j;
}
}
}
bfs();
}
return 0;
}
~~~
- 前言
- The 12th Zhejiang Provincial Collegiate Programming Contest - D
- 用鄰接表存儲n個頂點m條弧的有向圖
- hdu 5289 Assignment(給一個數組,求有多少個區間,滿足區間內的最大值和最小值之差小于k)
- hdu 1358 Period(給定一個字符串,求有多少個前綴(包括自己本身),它是由k(k&gt;2,并且盡量大)個循環節組成的)
- hdu 1806 Frequent values(給定一個非降序數組,求任意區間內出現次數最多的數的次數)
- poj 3264 Balanced Lineup(查詢區間最大值與最小值的差)
- HDU 1010 Tempter of the Bone(DFS+奇偶剪枝)
- HDU 1015 Safecracker(第一次用了搜索去遍歷超時,第二次用for循環可以了,思路一樣的)
- HDU 1016 Prime Ring Problem(DFS)
- HDU 1026 Ignatius and the Princess I(BFS+記錄路徑)
- HDU 1072 Nightmare(BFS)
- HDU 1237 簡單計算器(后綴式+棧)