HTW Berlin
Fachbereich 4
Internationaler Studiengang
Internationale Medieninformatik (Bachelor)
Info 2: Informatik II
Winter Term 2010/11
Exercise 14: It's Déjà vu all over again!1
Lab exercises:
How do you go about reading in characters from a file in C++? Write and test a
method that returns the next character in a file. Note that you have to do
something with the carriage returns - such as ignoring them - and that you
have to decide what to do when there are no characters to be returned.
How do you write a string to a file? How do you write an integer to a file?
A character? How do you create a file, anyway?
Now the fun begins! Write a C++ application to read in a file character
by character, counting the frequencies with which each character occurs. When
there are no more characters, create a file frequency.txt
and output the frequencies for each character. You should be able to deal with German texts.
Output a histogram of the character frequencies. One simple kind of histogram has horizontal lines proportional to the magnitude of the number it represents. For example:
A : **********
B : *****
C : ******
Now make your histogram application display the histogram
with vertical lines and input the file name as a parameter.
(For the bored) How do you deal with Unicode in C++? Can you make a histogramm for GIF-encoded pictures?
Your report is due by 11.00 pm the night before your next lab!
1 Attributed to Yogi Berra, a famous American baseball player