Functions are core part of programming in procedure-oriented programming (POP). Most of the times, we have to sort out the problem statement we get to solve. Now in such cases, following a modular approach for solving the problem in POPs is always preferable. This presentation discuss the topic of functions with an example. Thanks for watching the presentation

1. Functions
Programming concept | Example oriented explanation
Prerequisites: Basic knowledge of C, C++ or any programming language

2. Mr. Ajay and his business problem
Mr. Ajay, a brand-new
entrepreneur own a car-
rental business
He is the only person who manage
his business.
He is like a MAIN() FUNCTION of a
C or C++ program. Every task that
happens in his business is done by
him. Currently, nobody is helping
him to work.
After some weeks, Mr. Ajay is facing
traumatic situations. He is not able
to do all the tasks at a time as a
single human and now there are
some errors occurring because of
him.
He has been recommended by a
business consultant TO DIVIDE HIS
WHOLE TASK IN SMALL SET OF
SUBTASK, hire an employee that
can do it better, and assign him that
task.

3. Mr. Ajay divided his business tasks
Now, Mr. Ajay got
the point of
business and he
divided his work in
following way
RENT RECORD KEEPING
1. Get the details of car which
was ordered for rent
2. Enter and save details of car
and details of tenant in Excel
sheet
3. Complete the payment
4. Print the payment
5. Give a copy of receipt to
mechanic
6. Report it to manager
MECHANIC
1. Receive the car details from
record keeping
2. Pick up the car from car park
3. Drive the car to the tenant's
house
4. Give the copy of receipt to
tenant
5. Return to the work back
CAR CLEANER
1. Check the dirty cars in car park
2. Collect the required tools from
cleaning wardrobe
3. Clean dirty cards thoroughly
4. Put the tools back to their place
PAYROLL MANAGER
1. Check the current month
2. Pick up each employee
from the list
3. For each employee,
calculate their monthly
payment amount
4. Send the amount to the
specified employee's bank
account
5. Keep record of payment
6. Return payment reports to
manager
MANAGER MR. AJAY HIMSELF
1. While the working hours are on:
2. Collect car rent details
3. Save it in excel sheet
4. Ask the car cleaner to clean cars
if more than 10 cars are dirty
5. If this is month end, ask payroll
manager for payment reports
6. At end of the day, calculate the
business profit
7. Save those details
8. Exit from office

4. Mr. Ajay is free from traumatic situations
Now, the Mr. Ajay is free from trauma
of work because he must only keep
track of specific tasks and all other
tasks are divided into subtasks and
assigned to each employee.
Now, Mr. Ajay's business is touching the heights
because he learnt great management skills, but he
didn't know it was like
USING FUNCTIONS IN PROGRAMMING.
Did you find anything regarding the types of functions? Let’s see a summary
In his business, every FUNCTION (employee)
works when HE CALLS THE FUNCTIONS to do
that work.

5. How were the idea of functions used?
THE RECORD KEEPING
is like Function with parameter and
return value as he accept an order
from tenant and returns the receipt to
the mechanic to send the car to
tenant's house.
Types of functions
A function refers to dividing a large task into pieces of code. A function take parameters and can return values optionally.
THE MECHANIC
is like Function with parameter and
no return value because he accepts
the receipt from record keeping but
doesn't return anything to record
keeping; only drop the car to target
tenant.
Function with parameter,
and return value
Function with parameter,
but no return value
Function with no
parameter, but return
value
Function with no
parameter, no return
value
CAR CLEANER
is like Function with no parameter, no
return value as once he is called to clean
cars, he automatically does his work and
no need to tell or return anything to his
caller
THE PAYROLL MANAGER
is like Function with no parameter
but return value as he only was called
to get reports of payment. Rest of
payment task he does on himself and
returns the payment reports to the
manager Mr. Ajay.
MR. AJAY THE MANAGER is like still a MAIN FUNCTION as he keeps track of people of his business for a day. He also check for certain
conditions like necessity for cleaning car and completing payment every month.
HENCE, THIS IS WHAT A FUNCTION IS AND ITS TYPES IN PROGRAMMING