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// 3026 Borg Maze// Time Limit: 1000MS Memory Limit: 65536K// Total Submissions: 2827 Accepted: 888#include<iostream>#include<queue>#define MAXN 105#define N 55#define INF 10000000using namespace std;struct node
{
int x,y; int step;
};int dir[4][2]={{-1,0},{0,-1},{0,1},{1,0}};char maze[N][N];bool vis[N][N];int g[MAXN][MAXN],v[N][N];node d[MAXN];int n,m,cnt;void BFS( node a ){ int i,x,y,nx,ny,step; node p; queue<node> que; memset( vis, false, sizeof(vis) ); que.push( a ); vis[a.x][a.y]=true; while( !que.empty( ) )
{ p=que.front( ); que.pop( ); x=p.x,y=p.y,step=p.step+1; for( i=0; i<4; i++ ) { nx=x+dir[i][0],ny=y+dir[i][1]; if( nx<m && nx>=0 && ny<n && ny>=0 && !vis[nx][ny]) { if( maze[nx][ny]=='S' || maze[nx][ny]=='A' ) { g[v[a.x][a.y]][v[nx][ny]]=g[v[nx][ny]][v[a.x][a.y]]=step; p.x=nx,p.y=ny,p.step=step; que.push( p ); vis[nx][ny]=true;
} if( maze[nx][ny]==' ' ) { p.x=nx,p.y=ny,p.step=step; que.push( p ); vis[nx][ny]=true; } } } }}void create_graph( ){ int i,j; for( i=0; i<m; i++ ) gets( maze[i] ); cnt=0; for( i=0; i<m; i++ ) for( j=0; j<n; j++ ) if( maze[i][j]=='A' || maze[i][j]=='S' ) d[cnt].x=i,d[cnt].y=j,d[cnt].step=0,v[i][j]=cnt++; for( i=0; i<cnt; i++ ) for( g[i][i]=0, j=i+1; j<cnt; j++ ) g[i][j]=g[j][i]=INF; for( i=0; i<cnt; i++ ) BFS( d[i] );}int prim( ){ int i,j,k,min,ans; int dis[MAXN]; for( i=0; i<cnt; i++ ) dis[i]=g[0][i]; ans=0; for( i=1; i<cnt; i++ ) { min=INF,k=-1; for( j=0; j<cnt; j++ ) if( dis[j] && dis[j]<min ) min=dis[j],k=j; ans+=min; dis[k]=0; for( j=0; j<cnt; j++ ) if( dis[j] && g[k][j]<dis[j] ) dis[j]=g[k][j]; } return ans;}int main( ){ int ans,t; char c[100]; scanf("%d",&t); while( t-- ) { scanf("%d%d",&n,&m); gets( c ); create_graph( ); ans=prim( ); printf("%d\n",ans); } return 0;}AmazingCaddy 2010-03-16 22:47 鍙戣〃璇勮
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