求助！ vis数组无法输入

#include<iostream>
#include<queue>
#include<vector>
using namespace std;
struct node{
	int x;
	int y;
};
vector<char>a[100005];
vector<bool>vis[100005];
queue<node>q;
int dx[]={1,-1,0,0};
int dy[]={0,0,1,-1};
int n,m;
int sx,sy;
int my[999];
void bfs(){
	sx+=1;
	q.push(node{sx,sy});
	vis[sx][sy]=1;
	int cnt=my[a[sx][sy]];
	while(!q.empty()){
		for(int i=0;i<4;i++){
			int xx=q.front().x+dx[i];
			int yy=q.front().y+dy[i];
			if(xx>=1 && xx<=n && yy>=1 && yy<=m && a[xx][yy]!='*' && !vis[xx][yy]){
				vis[xx][yy]=1;
				cnt+=my[a[xx][yy]];
				cout<<cnt<<endl;
				q.push(node{xx,yy});
			}
		}
		q.pop();
	}
	cout<<cnt;
}
int main(){
	my['S']=1,my['M']=5,my['L']=10;
	int n,m;
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=m;j++){
			char x;
			cin>>x;
			a[i].push_back(x);
			vis[i].push_back(false);
		}
	}
	cin>>sx>>sy;
	bfs();
	return 0;
}