逃离迷宫（广搜50行代码）

题解:

#include <bits/stdc++.h>
using namespace std;
const int N = 25;
char a[N][N];
int n,m,to[4][2]={-1,0,1,0,0,-1,0,1};	
bool vis[N][N];
struct node{
	int x,y,step;
};
void bfs(int x,int y,int s){
	int flag=0;
	queue<node> q;
	node u;
	q.push({x,y,s});
	vis[x][y]=1;
	while(!q.empty()){
		u = q.front();
		if(a[u.x][u.y] == '*'){
			cout<<u.step<<endl;
			flag = 1;
			break;
		}
		q.pop();
		for(int i=0;i<4;i++){
			int nx=u.x+to[i][0];
			int ny=u.y+to[i][1];
			if(nx <= 0 || ny <= 0 || nx > n || ny > m || a[nx][ny] == '#' || vis[nx][ny])continue;
			q.push({nx,ny,u.step+1});
			vis[nx][ny]=1;
		}
	}
	if(!flag)cout<<-1<<endl;
}
int main(){
	
	int x, y;
	while(cin>>n>>m){
		if(n==0 && m==0)break;
		memset(vis,0,sizeof(vis));
		for(int i=1;i<=n;i++){
			for(int j=1;j<=m;j++){
				cin>>a[i][j];
				if(a[i][j] == '@')x=i,y=j;
			}
		}
		bfs(x,y,0);
	} 
	
	return 0;
}