40分求助

#include<bits/stdc++.h>

//cout<<fixed<<setprecision(2);

using namespace std;

int d[4][2] = {{-1,0},{0,1},{1,0},{0,-1}};
char mp[115][17];
int vis[115][17];
 
bool f = false;
int n,m;

struct p{
	int x,y;
}path[10000000];
bool check(int x,int y){
	return x>=1 && x<=n && y>=1 && y<=m && mp[x][y] == '.' && !vis[x][y];
}
int k = 0,cnt = 0;
void dfs(int x,int y){
	if(x==n && y==m){
		for(int i = 0;i<k;i++){
			cout<<path[i].x<<" "<<path[i].y<<endl; 
		}
		return;
	}
	for(int i = 0;i<4;i++){
		int nx = x+d[i][0];
		int ny = y+d[i][1];
		if(check(nx,ny)){
			path[k++] = {nx,ny};
			vis[nx][ny] = 1;
			dfs(nx,ny);
			k--;
		}
	}
}

int main(){
	cin>>n>>m;
	for(int i = 1;i<=n;i++){
		for(int j = 1;j<=m;j++){
			cin>>mp[i][j];
		}
	}
	dfs(0,1);
	return 0;
}