Abstract
Write a simple character filter to "compress" a text sequence.
Details
The program should convert sequences of three or more repeated
characters (of all kinds, including special characters)
to a representation of the form ~nc where n is
the number (a single digit) of repeated characters and c is the
character. A single tilde (~) in the input should be output as a double
tilde. A double tilde in the input should be output as ~~~~. Sequences
of more than nine repeated characters must be broken up into two or more
sequences of 9 or less.
io:~% gcc -Wall -o p3 p3.c
io:~% ./p3
abbcddddeffgfff
abbc~4deffg~3f
a~bc55555
a~~bc~55
abbbbbbbbbbbbbbbbbbbc
a~9b~9bbc
~~
~~~~
~~~~
~4~
CTRL-D
io:~%
While illustrative of compression, the above does not reflect actual
end-of-line processing. The following is an actual transcript of
running one solution interactively:
ceres 2% ./p3
abbcddddeffgfff
a~bc55555
abbc~4deffg~3f
abbbbbbbbbbbbbbbbbbbc
a~~bc~55
~~
a~9b~9bbc
~~~~
~~~~
CTRL-D~4~
ceres 2% ./p3
hellllllllo worrrrrld
but this is the end
he~8lo wo~5rld~4
CTRL-Dbut this is the end
ceres 2%
Another valid example is the following, in which a different function
for reading characters was used:
[brian p3]$ ./p3
abbcddddeffgfff
abbc~4deffg~3fa~bc55555
a~~bc~55abbbbbbbbbbbbbbbbbbbc
a~9b~9bbc~~
~~~~~~~~
~4~CTRL-D
[brian p3]$
In both cases the same set of input lines was provided, but because
different system library functions were used, a different interactive
output was generated. However, the same sequence of characters was
generated to standard out in both cases.
Submission Requirements
- As usual, the program must be named p3.c and must reside in the
cse271.131/p3 subdirectory.
- Create and use an appropriate Makefile that will compile your program
using make, and will clean the directory with make
clean.
- Your name must be in the comment section.
- Do a touch DONE when the program is ready to be collected.