Homework 3 - Create your own Loop application

Create your own unique While-End or (For End) repetition C code. You decide the theme. Be sure to provide an overview of what your repetition structure is doing. Please keep the design simple for this exercise. Just a few lines of code is all that is needed for this response. This should be code you wrote for an application that is interesting to you. In other words, make it your own and have fun with it.

Provide the C code and a screen capture showing the results of testing your code in an online compiler. Be sure to test your code with several test cases and show your test case table.

Hands-On Lab

Overview

This hands-on lab allows you to follow and experiment with the critical steps of developing a program including the program description, analysis, test plan, design (using pseudocode), and implementation with C code. The example provided uses sequential, selection and repetition statements.

Program Description

This program will calculate the average of 10 positive integers. The program will ask the user to 10 integers. If any of the values entered is negative, a message will be displayed asking the user to enter a value greater than 0. The program will use a loop to input the data.

Analysis

I will use sequential, selection and repetition programming statements.

I will define two integer numbers: count, value and sum. count will store how many times values are entered. value will store the input. Sum will store the sum of all 10 integers.

I will define one double number: avg. avg will store the average of the ten positive integers input.

The sum will be calculated by this formula:

sum = sum + value

For example, if the first value entered was 4 and second was 10:

sum = sum + value = 0 + 4
sum = 4 + 10 = 14

Values and sum can be input and calculated within a repetition loop:

while count <10
Input value
sum = sum + value
End while
Avg can be calculated by:
avg = value/count

A selection statement can be used inside the loop to make sure the input value is positive.

If value >= 0 then
count = count + 1
Else
input value
End If

Test Plan

To verify this program is working properly the input values could be used for testing:

Pseudocode

// This program will calculate the average of 10 positive integers.
// Declare variables
Declare count, value, sum as Integer
Declare avg as double
//Initialize value
Set count=0
Set sum = 0
set avg = 0.0;
// Loop through 10 integers
While count < 10
Print "Enter a Positive Integer"
Input value
if (value >=0)
sum = sum + value
count=count+1
else
Print ("Value must be positive");
End if
End While
// Calculate average
avg = sum/count
// Print results
Print "Average is " + avg

C Code

The following is the C Code that will compile in execute in the online compilers.

// C code
// This program will calculate the sum of 10 positive integers.
// Developer: Faculty CMIS102
// Date: Jan 31, XXXX
#include
int main ()
{
/* variable definition: */
int count, value, sum;
double avg;
/* Initialize */
count = 0;
sum = 0;
avg = 0.0;
// Loop through to input values
while (count < 10)
{
printf("Enter a positive Integer\n");
scanf("%d", &value);
if (value >= 0) {
sum = sum + value;
count = count + 1;
}
else {
printf("Value must be positive\n");
}
}
// Calculate avg. Need to type cast since two integers will yield an integer
avg = (double) sum/count;
printf("average is %lf\n " , avg );
return 0;
}

Setting up the code and the input parameters in ideone.com:

Learning Exercises for you to complete

1. Change the code to average 20 integers as opposed to 10. Support your experimentation with screen captures of executing the new code.

2. Prepare a new test table with at least 3 distinct test cases listing input and expected output for the code you created after step 1.

3. What happens if you entered a value other than an integer? (For example a float or even a string). Support your experimentation with screen captures of executing the code.

4. Modify the code to allow the user to enter an unspecified number of positive integers and calculate the average. In other words, the user could enter number of positive integers. (Hint: You can prompt the user for how many they want to enter. Or; you could use a sentinel value to trigger when the user has completed entering values). You may need to conduct some research on your own to solve this problem. Prepare a new test table with at least 3 distinct test cases listing input and expected output for the code you created. Support your experimentation with screen captures of executing the new code.