There are 4 shapes on a 5x5 grid. Which shape is closest to the red square in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: red square at (1, 1)
Distance from target shape to purple square at (0, 0): 2
Distance from target shape to blue right_triangle at (1, 3): 2
Distance from target shape to gray rectangle at (4, 4): 6
Closest shape is the purple square at (0, 0) with distance 2</think>

<answer>(0, 0)</answer>