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:  6 5 4 3 2 7 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 8
Output: 3 2 7 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 8 6 5 4

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

Example 3:
Input:  0 9 5 5 8 2 8 6 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Output: 5 8 2 8 6 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 9 5

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