P7550 [COCI 2020/2021 #6] Bold

Paula wrote a letter to Daniel, and she needs to make the text bold so that Daniel, whose eyesight is getting worse, can read it. The letter can be represented as a matrix consisting of `.` and `#`. For every `#` originally in the letter, Paula needs to expand it to the lower-right into a $2 \times 2$ block of `#`.

The first line contains two integers $n, m$, representing the size of the letter. The next $n$ lines each contain $m$ characters, representing the content of the letter. It is guaranteed that there is no `#` in the last row and the last column.

Output $n$ lines, each containing $m$ characters, representing the letter after being made bold.

#### Constraints For $100\%$ of the testdata, $2 \le n, m \le 10^3$. It is guaranteed that the letter contains only `.` and `#`. ------------ #### Notes **The score of this problem follows the original COCI settings, with a full score of $50$.** **Translated from [COCI2020-2021](https://hsin.hr/coci/archive/2020_2021/) [CONTEST #6](https://hsin.hr/coci/archive/2020_2021/contest6_tasks.pdf) _T1 Bold_.** Translated by ChatGPT 5