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+## fiil it
+
+### Objectives
+
+Develop a program that receives only one parameter, a txt file which will contain a list of [**Tetrominos**](https://en.wikipedia.org/wiki/Tetromino) to assemble them in order to create the smallest square possible.
+
+### Instructions
+
+All files referring to the project, must be in the same folder.
+
+The program must:
+
+- Be written in **GO**
+- Be compiled to be runned
+- Assemble all of the **Tetrominos** in order to create the smallest square possible
+- Show an error if the input doesn't correspond to a classic **Tetromino** piece
+- Not allow the rotation of the **Tetrominos**
+- Organize the **Tetrominos** by their apparition order in the file
+- Identify each **Tetromino** in the solution, by assigning different charactes to different **Tetrominos**
+- Have at least 2 **Tetrominos** in the text file
+
+Some notes:
+
+#### Example of a text File:
+
+```console
+#...
+#...
+#...
+#...
+
+....
+....
+..##
+..##
+```
+
+- If it isn't possible to form a perfect square, the program should leave spaces between the **Tetrominos**. For example:
+
+```console
+ABB.
+ABB.
+A...
+A...
+```
+
+
+
+- Among all the possible candidates for the smallest square, we only accpet the ones where **Tetrominos** is placed on their most upper-left position. In the example below, the program would choose option a).
+
+```console
+a) ABB.  b)A...  c)A...
+   ABB.    ABB.    A...   ...
+   A...    ABB.    ABB.
+   A...    A...    ABB.
+```
+
+## Usage
+
+```
+student@ubuntu:~/fill-it$ cat -e sample.txt
+...#$
+...#$
+...#$
+...#$
+$
+....$
+....$
+....$
+####$
+$
+.###$
+...#$
+....$
+....$
+$
+....$
+..##$
+.##.$
+....$
+$
+....$
+.##.$
+.##.$
+....$
+$
+....$
+....$
+##..$
+.##.$
+$
+##..$
+.#..$
+.#..$
+....$
+$
+....$
+###.$
+.#..$
+....$
+student@ubuntu:~/fill-it$ ./fillit sample.txt | cat -e
+ABBBB.$
+ACCCEE$
+AFFCEE$
+A.FFGG$
+HHHDDG$
+.HDD.G$
+student@ubuntu:~/fill-it$
+```
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