A conversation between User and Assistant. The user asks a question, and the Assistant solves it. The assistant first thinks about the reasoning process in the mind and then provides the user with the answer.
User: Find the common rule that maps an input grid to an output grid, given the examples below.

Example 1:
Input:  2 9 2 3 9 1 9 8 9 1 9 2 5 3 5 3 2 1 2 3 9 1 2 1
Output: 9 1 2 1 2 9 2 3 9 1 9 8 9 1 9 2 5 3 5 3 2 1 2 3

Example 2:
Input:  0 0 0 0 0 0 0 0 0 0 0 9 8 3 2 1 1 9 2 8 3 8 7 0
Output: 3 8 7 0 0 0 0 0 0 0 0 0 0 0 0 9 8 3 2 1 1 9 2 8

Example 3:
Input:  2 5 8 9 4 4 0 0 0 0 0 0 0 0 7 3 3 5 1 5 3 5 5 4
Output: 3 5 5 4 2 5 8 9 4 4 0 0 0 0 0 0 0 0 7 3 3 5 1 5

Below is a test input grid. Predict the corresponding output grid by applying the rule you found.
Input:
8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 7 1 9 2 7 5
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>.
Assistant: Let me solve this step by step.
<think>
user