There are 5 shapes on a 8x8 grid. Which shape is closest to the blue 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: blue square at (2, 4)
Distance from target shape to brown right_triangle at (4, 3): 3
Distance from target shape to red right_triangle at (5, 6): 5
Distance from target shape to green right_triangle at (4, 6): 4
Distance from target shape to gray trapezoid at (5, 5): 4
Closest shape is the brown right_triangle at (4, 3) with distance 3</think>

<answer>(4, 3)</answer>