There are 6 shapes on a 7x7 grid. Which shape is closest to the yellow 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: yellow square at (1, 5)
Distance from target shape to gray square at (0, 6): 2
Distance from target shape to red square at (5, 2): 7
Distance from target shape to brown rectangle at (1, 6): 1
Distance from target shape to pink trapezoid at (1, 2): 3
Distance from target shape to cyan right_triangle at (6, 0): 10
Closest shape is the brown rectangle at (1, 6) with distance 1</think>

<answer>(1, 6)</answer>