HDU 1026 Ignatius and the princess I (BFS)

Question Link

From (0, 0) to (N-1, M-1), ask at least time.

Ideas: BFs ,,,,,

 1 #include <stdio.h> 2 #include <string.h> 3 #include <queue> 4 #include <iostream> 5  6 using namespace std ; 7  8 struct node 9 {10     int x,y ;11     int tim ;12     friend bool operator < (node a,node b)13     {14         return a.tim > b.tim ;15     }16 } temp,temp1;17 int N,M ,t;18 char mapp[110][110] ;19 int vis[110][110] ;20 int dir[4][2] = {{-1,0},{1,0},{0,-1},{0,1}} ;21 22 int BFS()23 {24     temp.x = 0 ;25     temp.y = 0 ;26     temp.tim = 0 ;27     priority_queue<node>Q ;28     Q.push(temp) ;29    // vis[0][0] = true ;30     while(Q.size())31     {32         temp = Q.top() ;33         Q.pop() ;34         if(temp.x == N-1 && temp.y == M-1) return temp.tim ;35         for(int i = 0 ; i < 4 ; i++)36         {37             temp1.x = temp.x+dir[i][0] ;38             temp1.y = temp.y+dir[i][1] ;39             if(temp1.x >= 0 && temp1.y >= 0 && temp1.x <= N-1 && temp1.y <= M-1 && vis[temp1.x][temp1.y] == -1 && mapp[temp1.x][temp1.y] != ‘X‘)40             {41                 vis[temp1.x][temp1.y] = temp.x*M+temp.y ;42                 if(mapp[temp1.x][temp1.y] == ‘.‘)43                     temp1.tim = temp.tim+1 ;44                 else45                     temp1.tim = temp.tim + mapp[temp1.x][temp1.y]-‘0‘+1 ;46                 Q.push(temp1) ;47             }48         }49     }50     return -1 ;51 }52 void print(int x,int y)53 {54     if(x == 0 && y == 0)55         return ;56     int xx = vis[x][y]/M ;57     int yy = vis[x][y]%M ;58     print(xx,yy) ;59     printf("%ds:(%d,%d)->(%d,%d)\n",t++,xx,yy,x,y) ;60     if(mapp[x][y] >= ‘0‘ && mapp[x][y] <= ‘9‘)61     {62         while(mapp[x][y] -‘0‘ > 0)63         {64             printf("%ds:FIGHT AT (%d,%d)\n",t++,x,y) ;65             mapp[x][y] -- ;66         }67     }68 }69 int main()70 {71     while(~scanf("%d %d",&N,&M))72     {73         for(int i = 0 ; i < N ; i++ )74             scanf("%s",mapp[i]) ;75         memset(vis,-1,sizeof(vis)) ;76         int timee = BFS() ;77         if(timee == -1)78         {79             printf("God please help our poor hero.\nFINISH\n") ;80         }81         else82         {83             t = 1 ;84             printf("It takes %d seconds to reach the target position, let me show you the way.\n",timee) ;85             print(N-1,M-1) ;86             printf("FINISH\n") ;87         }88     }89     return 0 ;90 }

View code

 

HDU 1026 Ignatius and the princess I (BFS)