Robot Room Cleaner

Given a robot in a grid with obstacles, clean all reachable cells. The robot can move in 4 directions and can detect obstacles. The robot interface provides move() and turnLeft()/turnRight() methods.

Examples
Input: []
Output:
Hints

Robot Room Cleaner

Given a robot in a grid with obstacles, clean all reachable cells. The robot can move in 4 directions and can detect obstacles. The robot interface provides move() and turnLeft()/turnRight() methods.