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 4 1 6 4 6 5 6 9 0 0 0 0 0 0 0 0 0 0 0 1 5
Output: 1 6 4 6 5 6 9 0 0 0 0 0 0 0 0 0 0 0 1 5 2 4

Example 2:
Input:  6 2 9 3 3 0 0 0 0 0 0 0 0 0 0 0 4 7 7 3 2 1
Output: 9 3 3 0 0 0 0 0 0 0 0 0 0 0 4 7 7 3 2 1 6 2

Example 3:
Input:  5 2 9 9 7 9 9 1 4 6 5 0 7 3 7 4 5 7 2 3 2 1
Output: 9 9 7 9 9 1 4 6 5 0 7 3 7 4 5 7 2 3 2 1 5 2

Below is a test input grid. Predict the corresponding output grid by applying the rule you found.
Input:
0 0 0 0 0 7 6 9 7 9 1 2 3 1 1 9 4 7 8 2 8 0
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