Algorithm & Flow Charts

Presented ByManesh TCourse:1090 CS

ALGORITHMS AND FLOWCHARTS

Algorithm Step by step method to solve a problem is algorithm

Flow Chart Diagrammatic representation of algorithm

Algorithm

Example 1:

Write an algorithm to Add two numbers

Problem: Add two numbers

Step 1: Start Step 2: Read A, B

Step 3: C=A+B Step 4: Print C Step 5: Stop

AlgorithmProblem: Multiply 2 numbersStep 1: StartStep 2: Read A, BStep 3: C=A*BStep 4: Print C Step 5: Stop

Problem: Subtract 2 numbers

Step 1: StartStep 2: Read A, BStep 3: C=A-BStep 4: Print C Step 5: Stop

AlgorithmProblem: 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

AlgorithmProblem: Find your Age Step 1: Start Step 2: Read Byear

Step 3: Age=2015-Byear Step 4: Print Age

Step 5: Stop

AlgorithmProblem: Area of Circle Step 1: Start Step 2: Read Radius

Step 3: Area=3.14*Radius *Radius Step 4: Print Area

Step 5: Stop

AlgorithmProblem: Find even or odd

Step 1: Start Step 2: Read N

Step 3: Is (N%2=0) thenPrint “Even”

elsePrint “Odd”

Step 4: Stop

Detailed Algorithm Step 1: Start Step 2: Read M1,M2,M3,M4

Step 3: GRADE M1+M2+M3+M4Step 4: Is (GRADE < 60) then

Print “FAIL” else

Print “PASS”Step 5: Stop

AlgorithmProblem: Find Pass or Fail

The FlowchartA Flowchart is another algorithm but graphical.

shows logic solutionemphasizes individual steps and their

interconnectionsA flowchart must have a start and stopA steps in a flowchart must connect.

Flowchart Symbols General Used Symbols

Flow Chart: Add Two NumbersStart

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

isA>B

Y N

Print A Print B

Flow Chart: Find Even or OddStart

Read N

Print “Odd”

Stop

Print “Even”

IsN%2=0

NY

Flow Chart: Find Largest of two numbersStart

Read A, B

Print “B is large”

Stop

Print “A is large”

IsA>B

NY

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

Reada, 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. Workout various assignment problems Approach me for any doubt clarifications

Control Statements

Decision Making &Branching

Decision Making &Looping

If Statement Switch ConditionalStatement

Simple If

If else Nested if else

If else ladder

For loop

Do while loop

While loop

Jump

Break Continue