Upload
frankie-jones
View
262
Download
0
Tags:
Embed Size (px)
Citation preview
Types of Algorithm
• Once you fully understand the problem and have clarified any questions you have, you need to develop your solution.
• Algorithm is a set of instructions for the computer• Setting up the algorithms is probably the hardest
part of problem solving on the computer• The instructions cannot assume anything, cannot
skip steps, must be executable one step at a time and must be complete
Example 1:
Below is the algorithm to explain the morning activity for an employee, before going to the office.
1. Get up from bed2. Shower3. Get dressed4. Have breakfast5. Drive to the office
Types of Algorithm
Types of Algorithm
• Example 2:
Algorithm to solve the problem of calculating the average of 3 numbers.
1. Set Total=0, Average=0;
2. Input number1, number2, number3
3. Calculate sum of all 3 numbers using
formula:
Total = number1+number2+number3
Calculate average using the formula:
Average = Total/3
5. Print Average
Types of Algorithm
• Example 3:
Write an algorithm to solve the problem below:
Calculate the salary of an employee who works hourly basis. The formula to be used is Salary = hour works * pay rate
Types of Algorithm
Answer:
1. Input the hours work and pay rate
2. Calculate salary using the formula:
Salary= hours work x pay rate
3. Print Salary
Types of Algorithm
• Example 4:
Write an algorithm to solve the problem of calculating the area for a circle based on problem analysis given below:
Problem Analysis:Input : radius of circle
Process : Calculate area for a circle using the formula -
Area of circle= 3.14 x radius x radius
Output: Area of circle
Types of Algorithm
Answer:
1.Input radius of circle
2.Calculate area of a circle using formula:
Area of circle= 3.14*radius*radius
3. Print Area of circle
Pseudo Code
• Uses English like statements in place of the
flowchart graphical symbols. • It is easier to code a program from it than
from flowchart. • It is not tied to any programming language.• It is easy to modify but not graphical, difficult
to use for logically complex problems, and slower to create.
Pseudo Code
• Close to the actual language the programmer will be using
• Pseudocode is a compact and informal high-level description of a computer programming algorithm that uses the structural conventions of a programming language, but is intended for human reading rather than machine reading.
Pseudo Code
• typically omits details that are not essential for human understanding of the algorithm, such as variable declarations, system-specific code and subroutines.
• No standard for pseudocode syntax exists, as a program in pseudocode is not an executable program
• Example 1– Write a pseudo code to calculate the total of 3
numbers entered by user.
Start Program
Start Program START
Input number1, number2, number3
Sum = number1+ number2 + number3
Print SumENDEnd
Program
End Program
Display output on the screen
Display output on the screen
Instruction “input” tells the computer to obtain 3 numbers from user and
save it into variable number1, number2 and number3
Instruction “input” tells the computer to obtain 3 numbers from user and
save it into variable number1, number2 and number3
Instruction that tells the computer to add the 3
numbers
Instruction that tells the computer to add the 3
numbers
Pseudo Code
Pseudo Code
• Example 2:
Write a pseudo code to solve the problem below:
Calculate the salary of an employee who works hourly basis. The formula to be used is Salary = hour works * pay rate
Pseudo Code
Answer:
START
Input hours _work, pay_rate
Salary= hours_work * pay_rate
Print Salary
END
Pseudo Code
• Example 3:
Write a pseudo code to solve the problem of calculating the area for a circle based on problem analysis given below:
Problem Analysis:Input : radius of circle
Process : Calculate area for a circle using the formula -
Area of circle= 3.14 x radius x radius
Output: Area of circle
Pseudo Code
Answer:
START
Input radius_of_circle
Area_of_circle= 3.14*radius*radius
Print Area_of_circle
END
Flowchart
• graphic representations of the algorithm• shows the flow of processing from the
beginning to the end of a solution• each block in a flowchart represents one
instruction from an algorithm• Flow lines indicate the direction of the data
flow
Flowchart
• Symbols usedSymbol Function
Start/ end
process
Input/ output
condition
Flow lines
connector
Flowchart
• Example 1:
Draw a flow chart based on the problem given below:
Calculate the salary of an employee who works hourly basis. The formula to be used is Salary = hour works * pay rate
Case Study
Write the Problem Analysis, algorithm, pseudo
code and draw a flowchart based on the problem
given.
Question:You had bought a nice shirt with 15% discount. Count the
nett price for the shirt