hdu 1072

因为0<=n,m<=8的,所以广搜是没有问题的,题目规定每个点可以重复走,只需要将数值为4的点标记就可以了.

#include <iostream>#include <cstdio>#include <queue>#include <cstring>const int maxn = 10;using namespace std;struct node{   int x,y;   int time;   int ans;};int dir[4][2] = {{0,1},{1,0},{0,-1},{-1,0}};int map[maxn][maxn];int vis[maxn][maxn];int x1,y1;int row,col;int dfs(){     queue<node> que;     node t;     memset(vis,false,sizeof(vis));     t.time = 6;     t.ans = 0;     t.x = x1 , t.y = y1;     que.push(t);     while(!que.empty()){         t = que.front();         que.pop();         node temp = t;         if(map[temp.x][temp.y] == 3  && temp.time > 0)            return temp.ans;         for(int i = 0; i < 4; ++i){             temp.x = t.x + dir[i][0];             temp.y = t.y + dir[i][1];             temp.time = t.time - 1;             if(temp.x>0 && temp.x<=row && temp.y>0 && temp.y<=col && map[temp.x][temp.y] && !vis[temp.x][temp.y] && temp.time){                  temp.ans = t.ans + 1;                  if(map[temp.x][temp.y] == 4 ){                      temp.time = 6;                    vis[temp.x][temp.y] = true;                  }                  que.push(temp);             }         }     }     return -1;}int main(){    int cas;    scanf("%d",&cas);    while(cas--){        scanf("%d %d",&row,&col);        for(int i = 1; i <= row; ++i)         for(int j = 1; j <= col; ++j){               scanf("%d",&map[i][j]);               if(map[i][j] == 2)                    x1 = i , y1 = j;         }         int ans;         if((ans = dfs()) != -1)           printf("%d\n",ans);         else           printf("-1\n");    }    return 0;}