CF1098B Nice table
Description
You are given an $ n \times m $ table, consisting of characters «A», «G», «C», «T». Let's call a table nice, if every $ 2 \times 2 $ square contains all four distinct characters. Your task is to find a nice table (also consisting of «A», «G», «C», «T»), that differs from the given table in the minimum number of characters.
Input Format
First line contains two positive integers $ n $ and $ m $ — number of rows and columns in the table you are given ( $ 2 \leq n, m, n \times m \leq 300\,000 $ ). Then, $ n $ lines describing the table follow. Each line contains exactly $ m $ characters «A», «G», «C», «T».
Output Format
Output $ n $ lines, $ m $ characters each. This table must be nice and differ from the input table in the minimum number of characters.
Explanation/Hint
In the first sample, the table is already nice. In the second sample, you can change 9 elements to make the table nice.