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:  7 6 3 8 5 7 4 9 5 9 4 4 7 1 7 9 5 6 6
Output: 6 3 8 5 7 4 9 5 9 4 4 7 1 7 9 5 6 6 7

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

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

Below is a test input grid. Predict the corresponding output grid by applying the rule you found.
Input:
4 6 2 2 4 5 4 8 0 0 0 0 4 1 1 9 3 7 3
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