Check a Path Through Mutually Connected Street Tiles

### Problem Each grid tile has two street openings:1 left/right,2 up/down,3 left/down,4 right/down,5 left/up,and 6 right/up. Determine whether a continuous street path connects the top-left tile to the bottom-right. Neighboring tiles connect only when both expose openings toward each other. You cannot change tiles. ```cpp class Solution { public: bool hasValidPath(vector<vector<int>>& grid); }; ``` ### Examples **Example 1:** ```text Input: grid = [[1,1]] Output: true Explanation: The left tile opens right and the right tile opens left. ``` **Example 2:** ```text Input: grid = [[1],[1]] Output: false Explanation: Both tiles have only horizontal openings, so no vertical connection joins them. ``` ### Constraints - The rectangular grid has 1 to 300 rows and 1 to 300 columns. - Every tile value is in `[1,6]`, with the openings specified above. ### Contract considerations Keep the grid unchanged; the task asks existence, not the number or length of paths. ```hint Read the boundary condition Each step needs matching openings on both neighboring tiles. Check boundaries and a grid containing only one tile. ``` ### Boundary reminders Keep the grid unchanged; the task asks existence, not the number or length of paths.