Problem , Problem Solving, Algorithm & Flow Charts · Problem , Problem Solving, Algorithm & Flow...
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Transcript of Problem , Problem Solving, Algorithm & Flow Charts · Problem , Problem Solving, Algorithm & Flow...
Problem , Problem Solving,
Algorithm & Flow Charts
Presented By
Khozema Ali Shabbar
Course:101 CS
Problem and Problem Solving
Definitions
The state of feeling difficulty in completing any task is
called problem
The process of working through details of
a problem to reach a solution. Problem solving may
include mathematical or systematic operations and can
be a gauge of an individual's critical thinking skills.
Problem Solving Techniques
ALGORITHMS AND FLOWCHARTS Algorithm
Step by step method to solve a problem is algorithm
Flow Chart
Diagrammatic representation of algorithm
Divide and conquer strategy
A divide and conquer algorithm works
by recursively breaking down a
problem into two or more sub-
problems of the same (or related)
type, until solved
Mr.Mohammed Rahmath
Mr.Mohammed Rahmath
Steps in development of Algorithms
1. Problem definition
2. Development of a modal
3. Specification of Algorithm
4. Designing an Algorithm
5. Checking the correctness of Algorithm
6. Analysis of Algorithm
7. Implementation of Algorithm
8. Program testing
9. Documentation Preparation
Mr.Mohammed Rahmath
Algorithm
Problem: How to brush your teeth
Real life Example Step 1: Start
Step 2: Wake up
Step 3: Wash mouth
Step 4: Wash brush, apply toothpaste
Step 5: Brush your teeth
Step 6. Wash mouth and brush
Step 7: Put brush back to holder
Step 8: Stop
Problem: Add two numbers
Algorithm
Step 1: Start
Step 2: Read A, B
Step 3: C=A+B
Step 4: Print C Step 5: Stop
Algorithm Problem: Multiply 2
numbers
Step 1: Start
Step 2: Read A, B
Step 3: C=A*B
Step 4: Print C
Step 5: Stop
Problem: Subtract 2
numbers
Step 1: Start
Step 2: Read A, B
Step 3: C=A-B
Step 4: Print C
Step 5: Stop
Algorithm
Problem: Average of 3 numbers
Step 1: Start
Step 2: Read A, B, C
Step 3: Avg=(A+B+C)/3
Step 4: Print Avg Step 5: Stop
Algorithm
Problem: Find your Age
Step 1: Start
Step 2: Read Byear
Step 3: Age=2015-Byear
Step 4: Print Age
Step 5: Stop
Algorithm
Problem: Area of Circle
Step 1: Start
Step 2: Read Radius
Step 3: Area=3.14*Radius *Radius
Step 4: Print Area
Step 5: Stop
Algorithm
Problem: Find even or odd
Step 1: Start
Step 2: Read N
Step 3: Is (N%2=0) then
Print “Even”
else
Print “Odd”
Step 4: Stop
Detailed Algorithm
Step 1: Start
Step 2: Read Mark
Step 3: Is (Mark>=60) then
Print “PASS”
else
Print “Fail”
Step 4: Stop
Algorithm
Problem: Find Pass or Fail
The Flowchart A Flowchart is another algorithm but graphical.
shows logic solution
emphasizes individual steps and their interconnections
A flowchart must have a start and stop
A steps in a flowchart must connect.
Flowchart Symbols General Used Symbols
Flow Chart: Add Two Numbers Start
Read A, B
C=A+B
Print C
Stop
Algorithm
Flowchart
DECISION STRUCTURES
The expression A>B is a logical expression
it describes a condition we want to test
if A>B is true (if A is greater than B) we take the action on left
print the value of A
if A>B is false (if A is not greater than B) we take the action on right
print the value of B
DECISION STRUCTURES
is
A>B
Y N
Print A Print B
Flow Chart: Find Even or Odd Start
Read N
Print “Odd”
Stop
Print “Even”
Is
N%2=0
N Y
Flow Chart: Find Largest of two numbers Start
Read A, B
Print “B is large”
Stop
Print “A is large”
Is
A>B
N Y
Problem: Write Algorithm and Flowchart to find
solution of Quadratic equation
Algorithm: Step 1: Start
Step 2: Read a, b, c
Step 3: d sqrt ( )
Step 4: x1 (–b + d) / (2 x a)
Step 5: x2 (–b – d) / (2 x a)
Step 6: Print x1, x2
Step 7: Stop
START
Read
a, b, c
d sqrt(b x b – 4 x a x c)
STOP
x1 (–b + d) / (2 x a)
X2 (–b – d) / (2 x a)
4b b a c
Print X1, X2
Assignment 1
Draw algorithm and flowchart
1. Find area of triangle
(area=(1/2)*breadth*height)
2. Convert Celsius to Fahrenheit
temperature f = (1.8*c) + 32;
3. Volume of cylinder(V= 3.14*R*R*Height)
4. Find volume of sphere (4/3* 3.14*R*R*R)
5. Find biggest of three numbers.
Instructions to students
Study definition well
Study different algorithms well
Study how to draw flowchart for specific
problems.
Work-out various assignment problems
Approach me for any doubt clarifications