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dfs+bfs 120行#include <iostream>
#include <cstdio>
#include <cstring>
#include <string>
#include <queue>
using namespace std;
const int N=50;
char maze[N][N];
int visit[N*N];
int deep[N*N];
int ans,anss, sx,sy,ex,ey,m,n;
int dir_dfs[2][4][4][2]= {{{{0,-1}, {-1,0}, {0,1}, {1,0}},
{{-1,0}, {0,1}, {1,0}, {0,-1}},
{{0,1}, {1,0}, {0,-1}, {-1,0}},
{{1,0}, {0,-1}, {-1,0}, {0,1}}},
{{{0,1}, {-1,0}, {0,-1}, {1,0}},
{{1,0}, {0,1}, {-1,0}, {0,-1}},
{{0,-1}, {1,0}, {0,1}, {-1,0}},
{{-1,0}, {0,-1}, {1,0}, {0,1}}}};
int dir_bfs[4][2] = {{0,-1}, {-1,0}, {0,1}, {1,0}};
//d:当前方向
void dfs(int x, int y, int d, int step, int lr){
if(x==ex && y==ey){
ans = step;
return;
}
for(int i=0; i<4; i++){
int nx = x+dir_dfs[lr][d][i][0];
int ny = y+dir_dfs[lr][d][i][1];
if(!(nx>=0 && nx<m && ny>=0 && ny<n))
continue;
if(maze[nx][ny] == '#')
continue;
if(lr==0){
dfs(nx, ny, (d+i+3)%4, step+1, lr);
}else{
if(i==0 || i==2) dfs(nx, ny, (d+i+1)%4, step+1, lr);
else dfs(nx, ny, (d+i+3)%4, step+1, lr);
}
if(ans)
return;
}
}
void bfs(){
memset(visit, 0, sizeof(visit));
memset(visit, 0, sizeof(deep));
queue<int> q;
while(!q.empty()) q.pop();
int sxy = sx*n+sy;
q.push(sxy);
visit[sxy]=1;
deep[sxy]=1;
while(!q.empty()){
int t = q.front();
q.pop();
int x = t/n;
int y = t%n;
for(int i=0; i<4; i++){
int nx = x+dir_bfs[i][0];
int ny = y+dir_bfs[i][1];
int nxy = nx*n+ny;
if(!(nx>=0 && nx<m && ny>=0 && ny<n))
continue;
if(maze[nx][ny] == '#' || visit[nxy])
continue;
if(nx == ex && ny == ey){
anss = deep[t]+1;
return;
}
visit[nxy]=1;
deep[nxy] = deep[t]+1;
q.push(nxy);
}
}
}
int main(){
//freopen ("in.txt" , "r" , stdin);
//freopen ("out.txt" , "w" , stdout);
int icase;
cin>>icase;
while(icase--){
cin>>n>>m;
for(int i=0; i<m; i++){
for(int j=0; j<n; j++){
cin>>maze[i][j];
if(maze[i][j] == 'S') {sx=i;sy=j;}
if(maze[i][j] == 'E') {ex=i;ey=j;}
}
}
ans=0;
dfs(sx,sy,0,1,0);
cout<<ans<<" ";
ans=0;
dfs(sx,sy,0,1,1);
cout<<ans<<" ";
anss=0;
bfs();
cout<<anss<<endl;
}
return 0;
}
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