CMSC 104, Spring 2006

Homework 3

Your First C Program

Out:Thursday, March 9th
Due:Thursday, March 16th, before 11:59 p.m.

Note: No late projects will be accepted.

The Objective

To learn to use the gcc compiler
To become familiar with syntax error messages generated by the gcc compiler

The Task

For the first part of the assignment, you must complete the program attached to this sheet (to be distributed in class) by filling in the blanks where pieces of code are missing. After filling in the blanks, you are ready to move on to the second part of the assignment. For the second part, use a text editor to type in the C program. Type it in EXACTLY AS SHOWN, including all spacing. (Two exceptions in the header comment: 1) insert YOUR name as the author and 2) insert YOUR e-mail address.) Make sure to save the program with the file name hw3.c.
Compile the program using the command

Correct any compilation errors (if any) that you receive and recompile until you receive no errors.
Look at your directory to make sure that the file a.out is there. This is your executable program.
Run the program a few times using different sets of numbers to be sure that it works. To run your program, type a.out at the prompt. You can assume the user will only input positive integers. Here is a sample run of the program:

Submitting the Program

You do not have to turn in the sheet you used to fill in the blanks. However, you do have to submit your source code. Your C source code file MUST be called hw3.c. To submit your project, type the following at the Unix prompt. Note that the project name starts with uppercase 'H'. submit cs104 Hw3 hw3.c To verify that your project was submitted, you can execute the following command at the Unix prompt. It will show the file that you submitted in a format similar to the Unix 'ls' command. submitls cs104 Hw3

The Program

/************************************************************** ** Filename: hw3.c ** Author: put your name here ** Date Written: 10/12/05 ** Section: put your section here ** E-mail: put your umbc e-mail address here ** Description: This program reads two integers numbers in ** from the user and perfoms some statistical ** analysis on the numbers. **************************************************************/ #include _____________ int main() { int _______ = 0; /* Stores the first number */ int _______ = 0; /* Stores the second number */ float average = 0.0; /* Stores the average of both numbers */ /* Read in an integer from the user */ printf("Please enter an integer: "); scanf("______", ________); /* Read in another integer from the user */ printf("Please enter another integer: "); scanf("______", ________); /* Determine which number is larger */ if( ________ > _______ ) { printf("%d is larger than %d.\n", _________, __________); } else if ( ___________ > ____________) { printf("%d is larger than %d.\n", _________, __________); } else { printf("%d and %d are equal. \n", _________, __________); } /* Determine the average of the two integers */ average = ___________________ / 2.0 ; /* Print the average */ printf("The average of %d and %d is _______.\n", num1, num2, average); return _________; }