The document discusses the problem-solving process in computing, detailing stages like problem definition, algorithm development, and flowchart creation. It highlights the importance of these stages in accurately solving problems while providing examples of algorithms and flowcharts for various tasks. The document also defines common symbols used in flowcharts and their respective functions.

1. Algorithm and Flowchart
Dhanik Mahehswari
dhanikvikrant@gmail.com
Civil engineering department
QUEST Nawabshah

2.  In order to solve any problem by using computer, it is
very imperative to
 Detail the precise problem
 Itemizing the configuration
 The process of solving problem is known as “Problem
analysis”
Problem Solving Stages

3.  A problem solving process consists of eight stages as:
 Defining the problem
 Algorithm
 Flowchart
 Coding
 Input Preparation
 Compilation
 Debugging
 Testing

4.  This step has a great importance in obtaining the correct
solution of the problem
 The solution of the problem depends upon the description
and understanding the problem.
 This requires analysis of the problem to find the nature of
the problem analysis of the input data and planning of the
output result.
 This step achieves following goals:
Defining the Problem

5.  Problem description
 Determination of the objective
 Analysis of the input data
 Planning of output

6.  Series of procedural steps required to solve a given problem
is called an algorithm.
 The construction of the algorithm is the stage which requires
steps or operations which collectively solve 'a given problem.
 An algorithm usually is in ordinary English language and use
some mathematical symbols, if it is possible to solve a given
problem in more than one ways
 The choice of particular algorithm depends upon various
such as its reliability, accuracy and ease of modification.
Algorithm

7.  One of the most important factor in the choice of an
algorithm is the time requirement to execute it (after it in
high level language) with the help of computer.
 The algorithm which will least time when executed by a
computer is considered the best.

8.  Write an algorithm to print given roll number and name.
 Step 1: Enter Roll number
 Step 2: Enter Name
 Step 3: Print Roll number
 Step 4: Print name
 Step 5: Stop
EXAMPLE 01

9.  Write an algorithm to print the first ten natural numbers.
 Step-I: Select a counter A
 Step-2: Initialize A as zero
 Step-3: Add 1 to A
 Step-4: Print A
 Step-5: If A <10 then go to step-3
 Step-6: Stop
EXAMPLE 02

10.  Write an algorithm to print the greatest number from two
given numbers.
 Step-I: Enter two numbers as A and B
 Step-2: If A > B then Print A and go to step 4
 Step-3: Print B
 Step-4: Stop
EXAMPLE 03

11.  Write an algorithm to print a table of a given number
 Step-1: Select two counters as B and C
 Step-2: Initialize the counters B and C as zero
 Step-3: Enter a, number of table as A
 Step-4: Add 1 to B
 Step-5: Multiply A to B and assign the result to C
 Step-6: Print A; B and C
 Step-7: Check the value of B; If B<1O then go to step-4
 Step-8: Stop
EXAMPLE 04

12.  Write-an algorithm to print square and cubes from 1 to 5
 Step-1: Select the counter A, B and C
 Step-2: Initialize B and C as zero
 Step-3: Initialize A as 1
 Step-4: Calculate B as A*A
 Step-5: Calculate C as A*A*A
 Step-6: Print A, B, and C.
 Step-7: Add 1 to A
 Step-8: Check the value of A; if A < 5 then go to step-3
 Step-9: Stop
EXAMPLE 05

13.  A flowchart is a pictorial representation of the steps of a
involved in the procedure of solving any problem.
 The first formal flowchart was designed by John Von
Neumann‘
 A flowchart is drawn before the program in written to
ensure the instructions will be logically integrated.
 A flowchart is not a complete program but It is an aid to
programming.
FLOWCHART

14.  There are two types of flowchart, which are
 System Flowchart
 Program Flowchart
 A system flowchart shows the flow of data throughout a
data process as well as the flow into and out system. The
system analyst will use such a design and to explain a
data processing system.

15.  Program flowchart is a pictorial representation of the
method and sequence, to be followed for solving a
particular problem.
 There are several sets of the symbols, which are
standardized by American National Standard Institute
International Standard Organization (ISO) to draw the
flowchart.
 Most commonly used symbols are Oval, Parallelogram,
Rectangle, Diamond, Arrows, Connectors.

16.  Oval
 This ‘symbol' is used for beginning or end of a flowchart.
Therefore, it is also named as “TERMINAL”
Start/End

17.  PARALLELOGRAM:
 This symbol is used for transfer of data between Central
Processing Unit (CPU) output devices.
 In the simple words we can say this symbol is used to
represent and output operations.
 Therefore, it is also known as INPUT/OUTPUT box.
INPUT/
OUTPUT

18.  RECTANGLE:
 This symbol is used to represent any arithmetic operation
or transfer of data.
 This symbol is also known as PROCESS box.
PROCESS

19.  DIAMOND:
 This symbol is used to test the condition or to ask
question and on the their answers that decide a definite
path from a number of alternatives
 This symbols is also known as DECISION BOX.

20.  ARROWS:
 This symbol is used to show the direction of the flow
 In a flowchart every line must have an arrow to indicate

21.  CONNECTORS:
 Connectors are used to join the different parts of a
flowchart.
 The use of connectors gives neat shape to the flowchart.
there are two types of connector which are known as:
(a) On page connector
(b) Off page connector

22.  (a) On Page Connector
 On page Connector is represented by small circles.
 In a flowchart whenever complexity in branching arises,
this connectors used to connect one process with an
other place

23.  (b) Off Page Connector
 This symbol is used for off page Connector.
 In a complicated problem, flowchart may run into several
pages. The part of the flowchart on different pages is
connected with the help of Off Page Connector.

24.  Write a program to read a number from
keyboard, calculate the square of the
number and display it on the screen.
 1: Beginning of the program
 2: Read the number from the keyboard
 3: Calculate square of the Number
 4: Print the Square of the Number
 5: Stop
END
START
READ
Number
CALCULATE
(Number)2
PRINT
(Number)2
EXAMPLE 01

25.  Write a program to reads a number from
keyboard, checks; whether number is positive
or negative, if the number is positive it is
printed as it , If number is negative then
absolute value of the number is printed.
 1. Beginning of program.
 2. Read the number from the keyboard.
 3. If N >0, go to step 7
 4. Determine absolute value of N and assign
the resulting value to A, go
 5. Assigning the value of N to A
 6: Print the value of A
 7. End of program.
EXAMPLE 02 START
INPUT
N
PRINT
A
N = |N|
NO
IF
N ≥ 0
A = N
YES
B
START
B

26.  Draw flowchart to print given roll number and name.
 Draw flowchart to print the first ten natural numbers.
 Draw flowchart to print the greatest number from two
given numbers.
 Draw flowchart to print a table of a given number
 Draw flowchart to print square and cubes from 1 to 5
EXERCISE

27.  Draw flowchart to solve equation ax+b=0. Execute
flowchart using following data (i) a=3, b=6 (ii) a=0, b=52
 Draw flowchart to convert given temperature in Celsius
scale into Fahrenheit scale (i) 20oC (ii) 40oC (iii) 0oC