// C code // This program will calculate the sum of 10 positive integers. // Developer: Faculty CMIS102 // Date: Jan 31, XXXX #include <stdio.h> #include <stdbool.h> // needed for the Boolean variable debug. int main () { /* variable definition: */ int count, value, sum; int err; float avg; bool debug; /* Initialize */ count = 0; sum = 0; avg = 0.0; debug = false; // Loop through to input values while (count < 10) { printf("Enter a positive Integer\n"); err = scanf("%d", &value); if (debug) printf(" err = %d\n",err); if (debug) printf(" value is %d\n " , value ); //note the value of debug if (value >= 0) { sum = sum + value; count = count + 1; } else { printf("Value must be positive\n"); } } // Calculate avg. // Since sum and count are both integers, this will give you an integer division // Hence, we need to either // Declare sum as a float or... // type cast sum as float (as shown below) avg = (float) sum/count; printf("sum is %d\n", sum); printf("average is %f\n " , avg ); return 0; } Week 4 Classroom Lecture This week, the new pseudo commands are the Loops (or Repetitive) statements: A Repetitive (or Loop) statement is how you would execute the same block of code multiple times until some exit condition is met. There three types of Loops statements that we will learn. A Loop may be one of two types – pre test or post test. In a pre-test loop, the conditional test must be True before the code enters the loop. In a post-test loop, the code enters the loop first and then the conditional test is performed at the end of the loop to determine whether to exit or not. The three Loop statements are:  Repeat  goes thru loop at least once  condition test is an exit conditional Until (condition is true) - post test – if condition is True, the code exits the loop  While (condition is true) - pre test – if the condition is True, the code enters the loop  condition test is an enter conditional End While  For (initialize; test condition; increment) -pre test – if the condition is True, the code enters the loop  condition test is an enter conditional  builtin initialize counter  builtin test condition – you can use constant, a variable, or an expression  builtin increment – the increment is done at the end of the loop End For NOTE: The module readings has the pseudo-code for a For loop as For i = 1 step 1 to n We will NOT use this nomenclature. NOTE: The module readings also has Input statement without a prompt (Write) to the user as to what to enter. This bad practice as the user will be sitting there and not know that he is supposed to enter something. Your Input statements should always be preceded by a prompt (i.e. Write statement) to the user.  Sentinel-controlled loop o a special value is used to exit the loop o this value is typically an invalid or il ...

1. // C code
// This program will calculate the sum of 10 positive integers.
// Developer: Faculty CMIS102
// Date: Jan 31, XXXX
#include <stdio.h>
#include <stdbool.h> // needed for the Boolean variable
debug.
int main ()
{
/* variable definition: */
int count, value, sum;
int err;
float avg;
bool debug;
/* Initialize */

2. count = 0;
sum = 0;
avg = 0.0;
debug = false;
// Loop through to input values
while (count < 10)
{
printf("Enter a positive Integern");
err = scanf("%d", &value);
if (debug) printf(" err = %dn",err);
if (debug) printf(" value is %dn " , value ); //note the
value of debug
if (value >= 0) {
sum = sum + value;
count = count + 1;
}

3. else {
printf("Value must be positiven");
}
}
// Calculate avg.
// Since sum and count are both integers, this will give you an
integer division
// Hence, we need to either
// Declare sum as a float or...
// type cast sum as float (as shown below)
avg = (float) sum/count;
printf("sum is %dn", sum);
printf("average is %fn " , avg );
return 0;
}

4. Week 4 Classroom Lecture
This week, the new pseudo commands are the Loops (or
Repetitive) statements: A Repetitive
(or Loop) statement is how you would execute the same block
of code multiple times until some
exit condition is met.
There three types of Loops statements that we will learn. A
Loop may be one of two types – pre
test or post test. In a pre-test loop, the conditional test must be
True before the code enters the
loop. In a post-test loop, the code enters the loop first and then
the conditional test is performed
at the end of the loop to determine whether to exit or not.
The three Loop statements are:
at least once

5. Until (condition is true) - post test – if condition is True, the
code exits the loop
- pre test – if the condition is True,
the code enters the loop
est is an enter conditional
End While
-pre test – if the
condition is True, the code
enters the loop
– you can use constant, a variable, or an
expression
– the increment is done at the end of the
loop
End For
NOTE: The module readings has the pseudo-code for a For loop
as For i = 1 step 1 to n
We will NOT use this nomenclature.
NOTE: The module readings also has Input statement without a

6. prompt (Write) to the
user as to what to enter. This bad practice as the user will be
sitting there and not know
that he is supposed to enter something. Your Input statements
should always be
preceded by a prompt (i.e. Write statement) to the user.
-controlled loop
o a special value is used to exit the loop
o this value is typically an invalid or illogical value such as -1
for a value that is typically
positive like age or cost
and is typically entered by the user to exit a loop
– occurs when your test conditional is never
met. Always, check your test
condition carefully.
-controlled loops
o the counter is usually an Integer

7. o Initialize the counter
o Increment/Decrement the counter
Example for each of the types of loops: Sum of integers from 1
to 10
Set J, sumJ = 0 //Always initialize your counter and variables
Repeat
Set J = J + 1 //Increment the counter
Set sumJ = sumJ + J // Add the current value of J to the sumJ
variable
Until (J == 10) //When J equals 10, the loop exits
Write (“sumJ is: “ + sumJ) //sumJ is: 55
Set J, sumJ = 0 //Always initialize your counter and variables
While (J < 10) //Enters the loop if J is less than 10
Set J = J + 1 //Increment the counter
Set sumJ = sumJ + J // Add the current value of J to the sumJ
variable
End While

8. Write (“sumJ is: “ + sumJ) //sumJ is: 55
// OR if you start with 1 … Notice the logic is slightly
different….
Set J = 1
Set sumJ = 0 //Always initialize your counter and variables
While (J <= 10) //Enters the loop if J is less than or equal to
10
Set sumJ = sumJ + J // Add the current value of J to the sumJ
variable
Set J = J + 1 //Increment the counter
End While
Write (“sumJ is: “ + sumJ) //sumJ is: 55
Set sumJ = 0 //Always initialize your counter and variables
For (J=1; J <= 10; J++) //J is initialized to 1, Enters the loop if
J is less than or equal to 10
Set sumJ = sumJ + J // Add the current value of J to the sumJ
variable
End While // J is incremented by 1 (i.e. J++)
Write (“sumJ is: “ + sumJ) //sumJ is: 55

9. Example: Sentinel-controlled loop
Set count, ageSum, avgAge = 0 // Initialize to 0
Set age = 1 //Always initialize your variables- need to set age to
1, so that it enters the loop
While (age > 0) //Enters the loop if age is greater than 0
Write (“Please enter your age, enter -1 to exit”) //Prompt the
user to enter age or -1 to exit
Input age //get the user input
If (age > 0) then //test the value of age, if greater than 0,
then process your code
Set count = count + 1 // increment loop counter, only if
valid age
Set ageSum = ageSum + age //accumulate the sum of the
ages
Endif
End While
//Calculate the average age
Set avgAge = ageSum / count //Calculate the average age

10. Example: Sentinel-controlled loop using a Boolean
Declare continueEntry AS Boolean
Declare count, age AS Integer
Declare ageSum, avgAge AS Float //Declare ageSum as Float
to avoid Integer division
Set continueEntry = True // need to set to True, so that it enters
the loop
Set count, ageSum, avgAge = 0 // Initialize to 0
Set age = 0 //Always initialize your variables
While (continueEntry) //Enters the loop if age is greater than 0
Write (“Please enter your age, enter -1 to exit”) //Prompt the
user to enter age or -1 to exit
Input age //get the user input
If (age > 0) then //test the value of age, if greater than 0,
then process your code
Set count = count + 1 // increment loop counter, only if
valid age
Set ageSum = ageSum + age //accumulate the sum of the
ages
Set continueEntry = True
Else
Set continueEntry = False //set Boolean to False to exit
the loop

11. Endif
End While
//Calculate the average age
If (count > 0) //Test count so that we
don’t have division by 0
Set avgAge = ageSum / count //Calculate the average age
Endif
1
CMIS 102 Hands-On Lab
// Week 4
Overview:
This hands-on lab allows you to follow and experiment with the
critical steps of developing a program including the
program description, Analysis, , Design(program design,
pseudocode), Test Plan, and implementation with C code. The
example provided uses sequential, repetition statements and
nested 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

12. 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.
The program will loop for 10 positive numbers, prompting the
user to enter a number.
I will define three integer variables: count, value and sum.
count will store how many times values greater than 0 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

13. count = count + 1
sum = sum + value
Else
input value
End If
2
Program Design:
Main
// This program will calculate the average of 10 integer numbers
// Declare variables
// Initialize variables
// Loop through 10 numbers
// Prompt for positive integer
// Get input
// test input value for gt 0
if (value > 0)

14. //Increment counter
//Accumulate sum
Else
// display msg to enter a positive integer
// Prompt for positive integer
// Get input
Endif
// End loop
//Calculate average
//Print the results (average)
End
Test Plan:
To verify this program is working properly the input values
could be used for testing:
Test Case Input Expected Output
1 1 1 1 0 1
2 0 1 3 2
Average = 1.2
2 100 100 100 100 -100
100 200 -200 200 200
200 200
Input a positive value
Input a positive value
average is 120.0

15. NOTE: test #2 has 12 input numbers because there are two
negative numbers.
3
Pseudocode:
Main
// This program will calculate the average of 10 positive
integers.
// Declare variables
Declare count, value, sum as Integer
Declare avg as double
//Initialize values
Set count=0

16. 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 ***”)
Print “Enter a Positive Integer”
Input value
End if
End While
// Calculate average

17. avg = sum/count
// Print results
Print “Average is “ + avg
End //End of Main
4
C Code
The following is the C Code that will compile in execute in the
online compilers.
#include <stdio.h>
#include <stdbool.h> // needed for the Boolean variable
debug.
int main ()

18. {
/* variable definition: */
int count, value, sum;
int err;
float avg;
bool debug;
/* Initialize */
count = 0;
sum = 0;
avg = 0.0;
debug = false;
// Loop through to input values
while (count < 10)
{
printf("Enter a positive Integern");
err = scanf("%d", &value); //note: err is the error code
returned by scanf.
if (debug) printf(" value is %dn " , value ); //note the
value of debug
if (debug) printf(" err = %dn",err); // note: err is the error
code returned by scanf.
if (value >= 0) {
sum = sum + value;
count = count + 1;
}
else {
printf("Value must be positiven");
}
}
// Calculate avg.
// Since sum and count are both integers, this will give you an
integer division
// Hence, we need to either
// Declare sum as a float or...

19. // type cast sum as float (as shown below)
avg = (float) sum/count;
printf("sum is %dn", sum);
printf("average is %fn " , avg );
return 0;
5
}
Setting up the code and the input parameters in ideone.com:
Note the input integer values are 1, 1, 1, 0, 1, 2, 0, 1, 3, 2 for
this test case.
You can change these values to any valid integer values to
match your test cases.
You should also test with a negative number to make sure the
positive integer logic works properly.
Note: the input data needs to be entered into the stdin window
separated by a space of new line.
6

20. Results from running the programming at ideone.com:
7
Learning Exercises for you to try:
8
1. Change the code to average 20 integers as opposed to 10.
Support your experimentation with screen captures
of executing the new code. What happens if you change the
formatter to %.2f printf("average is %.2fn " ,
avg );
2. 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. To
help in your analysis try as input 1 2 3 a 4 5
Hint: activate this line if(debug) printf(" value is %dn " ,
value ); after the scanf statement that reads in the
value. Activate by changing the value of debug.

21. Next try as input 1.1 2.2 3.3 4.4 5.5 6.6 7.7 8.8 9.9 10.5
What happens?
3. 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 any 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.
4. 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.
Submission
Submit a neatly organized word (or PDF) document that
demonstrates you successfully executed this lab on
your machine using an online compiler. You should provide a
screen capture of the resulting output.
Also, provide the answers, associated screen captures, C Code
and descriptions of your successful completion
of learning exercises 1, 2, 3 and 4.
The answers to the learning exercises, screen captures, C code
and descriptions can be included in the same

22. neatly organized document you prepared as you ran this lab.
Note the code can be embedded in the word
document. However; be sure all code compiles and runs
perfectly before submitting the document.
Submit the C-code for no. 3 as a separate .txt (or .c ) file.
Submit your document no later than the due date listed in the
syllabus or calendar.
Grading guidelines
Submission points
No. 1 Successfully demonstrates execution of this lab with
online compiler for
exercise no. 1. Includes a screen capture of executing the new
code.
2
No. 2 Describes what happens if you entered a value other than
an integer? Support
your experimentation with screen captures of executing the
code.
2
No. 3 Modifies the C code to allow the user to enter an
unspecified number of

23. positive integers and calculate the average. Submit C code (as .c
or .txt) file screen
captures of executing the code.
3
No. 4 Provides a new test table with at least 3 distinct test
cases listing input and
expected output your program. Should include at least one
negative value.
2
Document is well-organized, and contains minimal spelling and
grammatical errors. 1
Total 10
9