Assignment 1: Basic C programming

CSE109 
1
Systems Software
Assignment 1: Basic C programming
Assignment Objectives
Students should demonstrate the following abilities:
1. Use the C struct construct to define new data type
2. Use pointers to define input/output parameters in C functions
3. Write a complete C program that includes structures and functions to manipulate
pointers
Assignment
You are working problems in which you must display your results as integer ratios;
therefore, you need to be able to perform computations with common fractions and get results
that are common fractions in reduced form. You want to write a program that will allow you to
add, subtract, multiply, and divide several pairs of common fractions.
Define a C structure named fraction with two data members of type integer (numerator
and denominator) as given below:
typedef struct{
 int numerator;
 int denominator;
} fraction;
Define the following functions:
add_fractions and multiply_fractions – Both methods accept two input
parameters of type fraction and return the sum or the product of the input fractions
through one output parameter of type fraction. Subtraction of two fractions is performed
by changing the sign of the numerator of the second fraction and calling add_fractions.
Similarly, multiplication of two fractions is performed by inverting the second fraction and
calling multiply_fractions.
get_fraction – prompts the user for two integers and returns a structure of type
fraction. The denominator should not be negative or equal to zero.
print_fraction - accepts an input parameter of type fraction and prints the fraction in
the form numerator/denominator.
CSE109 Lehigh University Summer 2020
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find_gcd, - accepts two input parameters of type int and returns their greatest common
divisor (GCD) as an int.
reduce_fraction – accepts one input/output parameter of type fraction and reduces
the input fraction using the GCD of the numerator and the denominator.
invert_fraction – accepts one input/output parameter of type fraction and inverts it
(swap the numerator and the denominator).
Write a main method that interacts with the user to get two fractions and an operation and
prints the result of the operation as a reduced fraction. Your program should keep asking the
user if she/he wants to perform another operation until the user enters ’n'. You may add more
functions in your program if you want but the functions above are required.
A sample run of the program is provided below.
Enter a common fraction as two integers separated by a slash> 1/4
Enter a common fraction as two integers separated by a slash> 3/4
Select an operation (+, -, *, /)> +
1/4 + 3/4 = 1
Do you want to perform another operation? (y/n)> y
Enter a common fraction as two integers separated by a slash> 2/3
Enter a common fraction as two integers separated by a slash> 1/-2
Invalid input - denominator must be positive.
Enter a common fraction as two integers separated by a slash> -1/2
Select an operation (+, -, *, /)> *
2/3 * -1/2 = -1/3
Do you want to perform another operation? (y/n)> y
Enter a common fraction as two integers separated by a slash> 1/2
Enter a common fraction as two integers separated by a slash> 3/2
Select an operation (+, -, *, /)> ?
Invalid operation – must be (+,-,*, or /)
Select an operation (+, -, *, /)> /
CSE109 Lehigh University Summer 2020
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1/2 / 2/3 = 1/3
Do you want to perform another operation? (y/n)> y
Enter a common fraction as two integers separated by a slash> 9/4
Enter a common fraction as two integers separated by a slash> 5/2
Select an operation (+, -, *, /)> -
9/4 - 5/2 = -1/4
Do you want to perform another operation? (y/n)> n
Save your C program in a file named fraction.c and test it for different fractions and
operations. Submit fraction.c on courseSite.