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

<answer>(1, 3)</answer>