edU_text_editor

An old style text editor.

The file old_version_did_not_pass.c is a previous implementation that did not pass one test case because of time.

edU, or ed multiplies Undo

This project has been developed as part of the "Algoritmi e Principi dell'Informatica" course at Politecnico di Milano. It has been evaluated "30/30 cum laude".

A C program that represents a text editor, where you can add, remove, print lines and do undo or redo actions.

Input Format

The program expects its input from stdio with the following format.

NOTE: MAX length of a line: 1024. Commands are considered correct.

Addition of lines

To add a line to the editor, it is needed to write the lines after the ind1,ind2c instruction, and after the last line, write a '.'.

Example:

1,2c
First Line
Second Line
.

Deletion of a line

To delete lines, it is needed to use the following format: ind1,ind2d NOTE: if you try to delete lines that doesn't exists, the command will have no effect.

Printing lines

To print a group of lines, it is needed to use the following format:

ind1,ind2p

NOTE: if the line doesn't exists, it will print a '.'.

Undo action

In order to go back to a previous version, you can do the following command ind1u where ind1 is the number of version that you want to go back.

Redo Action

Like undo, the command to do a redo is the following one: ind1r

Example of the input stream:

1,2c
first line
second line
.
2,3c
new second line
terza riga
.
1,3p
1,1c
new first line.
1,2p
2,2d
4,5p
1,3p
4,5d
1,4p
3u
1,6p
1r
1,3p
q

Example of the output stream:

first line
new second line
third line
new first line
new second line
.
.
new first line
third line
.
new first line
third line
.
.
first line
new second line
third line
.
.
.
new first line
new second line
third line