Programming Assignment 5
Due March 27, 2015 at 11:59 PM
Objectives
• To gain experience with file input/output techniques
• To gain experience with formatting output
• To practice overall problem-solving skills, as well as general design of a program
Task
Write a program that reads a text file, then prints some statistical results about its contents to
an output file. The results will be primarily an analysis of the characters in the file, which will
include the frequency of occurrence of certain categories of characters, as well as the frequency of
occurrences of each of the letters of the alphabet.
Note that in most standard English text, certain letters typically appear with a higher frequency
than others. This kind of information has been used in setting up games like Scrabble (letter
frequencies and point values, etc), as well as more serious applications like decoding encrypted
messages and cyphers.
Details and Requirements
• Start by asking the user to input the name of the input file, and then to input the name
of an output file. Whenever the user enters a filename that cannot be opened (both in the
input and output cases), print an error message and ask the user to re-enter. (We’ve seen
several code examples in the course notes that illustrate this). The input file can be ANY file
containing plain text.
• Read the contents of the input file, and then print to the OUTPUT file the following information about the contents of the input file:
– A header stating a general heading and the name of the input file
– The total number of characters contained in the file
– A chart (with headings) where each row lists a category, the number of occurrences of
that category of character, and the percentage of the total file this makes up. These are
the categories:
∗
∗
∗
∗
Letters
White space
Digits
Other
– Note that the percentages in this chart should add up to 100%
– A heading “LETTER STATISTICS”
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– Another chart (again, with headings), listing a category, the number of occurrences
of that letter type, and the percentage of all LETTERS this comprises. This time,
the categories are Uppercase letters, lowercase letters, and then each for the individual
letters of the alphabet (i.e. 26 of them). So this chart will have 28 rows
∗ Note that the percentage of uppercase + lowercase should add up to 100%
∗ Also, the percentages of the 26 alphabet letters should add up to 100%
∗ Specifically, note that these are percentages of the total number of letters, NOT the
total number of characters in the file
• All percentages should be printed to two decimal places, along with a space and a % sign
afterwards. Example: 12.45 %
• Your headings and category labels should match mine (see example output files below). You
may use whatever field widths you like, as long as your charts line up in neat columns (i.e.
your spacing doesn’t have to match mine exactly)
• Category labels on your chart should be lined up on the left side of the words. All numbers
in your charts should be lined up on the right side.
• Hint: Instead of declaring 26 different variables to count each letter, consider using an array
of counters
Sample run 1:
Sample Input File
Hello. How are you?
I am 4 years old. My favorite color is blue.
Next year I will be 5.
Sample Execution:
Please enter the name of the input file.
Filename: file1.txt
Please enter the name of the output file.
Filename: out1.txt
Processing complete
Sample Output File
Statistics for file: file1.txt
------------------------------------------------Total # of characters in file:
90
Category
How many in file
% of file
---------------------------------------------------------------------Letters
61
67.78 %
White space
22
24.44 %
Digits
2
2.22 %
2
Other characters
5
5.56 %
LETTER STATISTICS
Category
How many in file
% of all letters
---------------------------------------------------------------------Uppercase
6
9.84 %
Lowercase
55
90.16 %
a
5
8.20 %
b
2
3.28 %
c
1
1.64 %
d
1
1.64 %
e
8
13.11 %
f
1
1.64 %
g
0
0.00 %
h
2
3.28 %
i
5
8.20 %
j
0
0.00 %
k
0
0.00 %
l
7
11.48 %
m
2
3.28 %
n
1
1.64 %
o
7
11.48 %
p
0
0.00 %
q
0
0.00 %
r
5
8.20 %
s
2
3.28 %
t
2
3.28 %
u
2
3.28 %
v
1
1.64 %
w
2
3.28 %
x
1
1.64 %
y
4
6.56 %
z
0
0.00 %
Sample run 2:
Sample Input File
The quick brown fox jumped over the lazy dog.
How lazy was he? Well, he was pretty darn lazy, I’ll tell you.
And speaking of the fox, why was he jumping over dogs anyways?
Didn’t he have anything better to do with his time?
When he checked his watch at 12:45 PM, 15 more foxes jumped over
the lazy dog, who so far had counted 100 sheep, 17 cats, and 2 rabbits.
Sample Execution
3
Please enter the name of the input file.
Filename: file2.txt
Please enter the name of the output file.
Filename: out2.txt
Processing complete
Sample Output File
Statistics for file: file2.txt
------------------------------------------------Total # of characters in file:
362
Category
How many in file
% of file
---------------------------------------------------------------------Letters
261
72.10 %
White space
73
20.17 %
Digits
12
3.31 %
Other characters
16
4.42 %
LETTER STATISTICS
Category
How many in file
% of all letters
---------------------------------------------------------------------Uppercase
9
3.45 %
Lowercase
252
96.55 %
a
21
8.05 %
b
4
1.53 %
c
6
2.30 %
d
14
5.36 %
e
30
11.49 %
f
5
1.92 %
g
6
2.30 %
h
22
8.43 %
i
11
4.21 %
j
3
1.15 %
k
3
1.15 %
l
10
3.83 %
m
6
2.30 %
n
12
4.60 %
o
19
7.28 %
p
7
2.68 %
q
1
0.38 %
r
10
3.83 %
s
13
4.98 %
t
19
7.28 %
u
6
2.30 %
4
v
w
x
y
z
4
12
3
10
4
1.53
4.60
1.15
3.83
1.53
%
%
%
%
%
Requirements
• No global variables, other than constants
• You may use any of these libraries:
– iostream
– iomanip
– fstream
– cctype
• Write your source code so that it is readable and well-documented
• Part of assessing readability and style will be how well you break your program into appropriate functions. Note: Breaking it up into functions makes for smaller, easier-to-code segments.
You’ll make your work easier if you do so.
• Your program should only use standard ANSI header files (make sure to follow the directions
exactly on the handout for creating Visual C++ projects, so that Windows-specific headers
like stdafx.h and conio.h are not placed into your file)
Submitting
Program submissions should be done through Blackboard under the Assignments tab. Program
submissions are due March 27 at 11:59 PM.
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