<|im_start|>system
You are a helpful assistant. You first think about the reasoning process in the mind and then provides the user with the answer.<|im_end|>
<|im_start|>user
Find the common rule that maps an input grid to an output grid, given the examples below.

Example 1:
Input:  9 9 3 9 1 6 6 0 0 0 7 6 6 7 1 7 2 9 5
Output: 9 3 9 1 6 6 0 0 0 7 6 6 7 1 7 2 9 5 9

Example 2:
Input:  4 2 1 5 5 7 1 4 6 9 1 8 9 5 3 3 1 8 9
Output: 2 1 5 5 7 1 4 6 9 1 8 9 5 3 3 1 8 9 4

Example 3:
Input:  2 5 3 6 2 3 2 5 6 9 0 0 0 0 0 0 0 0 5
Output: 5 3 6 2 3 2 5 6 9 0 0 0 0 0 0 0 0 5 2

Below is a test input grid. Predict the corresponding output grid by applying the rule you found.
Input:
2 3 0 0 0 0 0 0 0 5 8 6 9 5 8 6 1 9 2
Show your work in <think> </think> tags, and return the answer in <answer> </answer> tags with space between each number. For example <answer> 1 3 5 7 </answer>.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>
user