http://acm.hdu.edu.cn/showproblem.php?pid=1072
Nightmare
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 5438 Accepted Submission(s): 2700
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.
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.
题意简单:
直接BFS~
code:
#include <iostream> #include <queue> #include <cstring> #include <cstdio> using namespace std; int map[10][10]; int sx,sy,ex,ey, n, m; struct node { int x, y,step,time; }; int dx[]= {1,-1,0,0}; int dy[]= {0,0,1,-1}; int bfs() { int i; node first, next; queue<node> q; first.x =sx; first.y = sy; first.time = 6; first.step = 0; q.push(first); while(!q.empty()) { first = q.front(); q.pop(); for(i=0; i<4; i++) { next.x = first.x + dx[i]; next.y = first.y + dy[i]; next.step = first.step + 1; next.time = first.time - 1; if(next.x<0||next.x>=n||next.y<0||next.y>=m||map[next.x][next.y]==0||next.time==0) continue; if(map[next.x][next.y]==3) return next.step; if(map[next.x][next.y]==4) { next.time = 6; map[next.x][next.y] = 0; } q.push(next); } } return -1; } int main() { int T, i, j; scanf("%d",&T); while(T--) { scanf("%d%d",&n,&m); for(i=0; i<n; i++) for(j=0; j<m; j++) { scanf("%d",&map[i][j]); if(map[i][j]==2) sx=i,sy = j; else if(map[i][j]==3) ex=i,ey = j; } printf("%d\n", bfs()); } return 0; }