Programming Fundamentals * Pima Community College * CSC130 -- 6.8 Streams

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6.8 Streams

Looking through a stream of characters for a specific pattern or sequence is frequently done by computers. For an example, think about what a compiler does with a program. It needs to look for comments, operators, identifiers, and constants.

In this lab I want you to do a bit of text processing yourself. (Not quite a compiler for sure.) You can use your standard input, or if you wish to read ahead in your book and process the input from a file. Both approaches are fine. Extra credit will be given if you take the "UNIX" approach of looking on the command line for a file name, and if it exists use it, otherwise use the standard input (keyboard or redirected input).

Write a program that process an input stream doing the following:

Ignore all input on a line after the semicolon. The ";" will be used to mark off comments.
Counting the input lines. Including those that only have comments
Looking for and converting binary numbers. Keeping the last one for each line. Summing all of the last binary numbers on each line.
Counting letters (a-z and A-Z) on each line. Summing the total number of letters.
Counting digits (0-9) on each line. Summing the total number of digits.

After each line read it prints out the following information:

Whether or not binary number was found.
If a binary number was found, the decimal value of the last one.
The number of letters.
The number of digits.

At the end of the file print out the following totals:

The total number of lines.
The total of all of the last binary numbers.
The total number of letters.
The total number of digits.

Given the following example input.

This has a comment; And the comment is discarded. 101010010010
A hidden binary number 9991999; Of 1
1010109AAAA10; The last binary number is decimal 2

This output should be in the following format:

No Binary Number       15 Letters           0 Digits
               1       19 Letters           7 Digits
               2        4 Letters           9 Digits
3 Lines --------------------------------------------
               3       38 Letters          16 Digits

Test your program with the following sample data set. It is available by anonymous ftp at
ftp://red.cscwc.pima.edu/pub/csc130/stream.dat.

; This is the test date for the lab "Stream"
; Louis Taber  3/29/98
; CSC130  Pima Community College
                           ; Blank Line
ABCDEFGHIJKLMNOPQRSTUVWXYZ ; Uppercase letters
abcdefghijklmnopqrstuvwxyz ; Lower case letters
1234567890                 ; Digits - binary number: 0
11111111                   ; Binary number 255
1000000000000000           ; This may give you 
                           ;   a negative number (OK)
                           ;   Do you know why?
10101010a10101010b111      ; Last binary number: 7
[]|--+=*#@                 ; Some special symbols
The last Line

Turn in a copy of your program and its output when used with the above test data marked with:

Your name
TABER CSC130
Lab 6.8: Streams
The compiler and OS that you used.

Place the lab in the instructor hand in box in BUS R6E, the "terminal room".

Instructor: ltaber@pima.edu** Red's Home page** The Pima College Site