answer.code: In function ‘void solve()’:
answer.code:10:12: error: missing template arguments before ‘vis’
   10 |     vector vis(n+1, vector(m+1, vector<int>(2)));
      |            ^~~
answer.code:19:14: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   19 |         auto [x, y, op, step] = qe.front(); qe.pop();
      |              ^
answer.code:20:12: error: ‘vis’ was not declared in this scope
   20 |         if(vis[x][y][op]) continue;
      |            ^~~
answer.code:21:9: error: ‘vis’ was not declared in this scope
   21 |         vis[x][y][op] = 1;
      |         ^~~