Leetcode 2577. Minimum Time to Visit a Cell In a Grid

Find the minimum time to reach the bottom-right of an m×n grid where each cell specifies the earliest time it can be visited and each step to an adjacent cell takes 1 second (you may wait in place), or return -1 if unreachable. This is a shortest-path problem with time-dependent node availability—solve by computing earliest feasible arrival times per cell (e.g., with a modified Dijkstra/BFS that accounts for waiting).