basic problem solving csc 111. learning objectives in this lecture we will learn 1. basic steps for...
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BASIC PROBLEM SOLVING
CSC 111
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Computer Programming -1
Learning Objectives
In this lecture we will learn
1. Basic steps for designing computer program
2. Algorithm
3. Flow Chart
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Solving Problems Stages
1. Problem Definition Define the main Problem
2. Problem Analysis Determine the inputs, outputs, Arithmetic &
logic operations
3. Design Solution Identify the required step for computer to do
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Problem Definition
Write a Program to Print the Sum of two integer Numbers
Write a program to Print the Average of three integer numbers
Write a program to print the volume of a cube and the sum of it’s surfaces’ areas
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Problem Analysis
Write a Program to Print the Sum of two integer Numbers
Inputs :First NumberSecond Number
Operations :Summation = first + second
Output :The summation
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Problem Analysis
Write a program to Print the Average of three integer numbers
Inputs :First Number
Second Number
Third Number Operations :
Average = (first + second + third ) / 3 Output :
The Average
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Problem Analysis
Write a program to print the volume of a cube and the sum of it’s surfaces’ areas
Inputs :1. Side Length
Operations : Volume = side * side * side Surface area = ( side * side ) * 6
Output :1. The Volume
2. The surface area
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Solving Problems Stages
Problem Definition
Problem Analysis
Solution DesignDesign a solution for the problem by writing an algorithm or drawing a flow chart
Algorithm
Flow Chart
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Basic steps for designing a solution
Read all the inputs
Calculate operations
Print the output
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Algorithms
Write a Program to Print the Sum of two integer Numbers
1. Start the program2. Read the first number and save in the variable ( N1 )3. Read the second number and save in the variable ( N2 )4. Sum the both numbers and save the result in the
variable ( Sum ) Sum = N1 + N2 5. Print the variable ( Sum ) 6. End the program
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Algorithms
Write a program to Print the Average of three integer numbers
1. Start the program2. Read the first number and save in the variable ( num1 )3. Read the second number and save in the variable ( num2 )4. Read the third number and save in the variable ( num3 )5. Sum the three numbers and save the result in the variable
( result ) result = num1 + num2 + num36. Divide the variable ( result ) by 3 and save the result in
variable ( Average ) Average = result / 3 7. Print the variable ( Average )8. End the program
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Algorithms
Write a program to print the volume of a cube and the sum of it’s surfaces’ areas
1.Start the program
2.Read the length of the side and save in variable ( Length )
3.Volume = Length * Length * Length
4.Surface = ( Length * Length ) * 6
5.Print the variable ( Volume )
6.Print the variable ( Surface )
7.End the program
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Flow Chart
Java Programming: From Problem Analysis to Program Design, Third Edition
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Flow chart’s Symbols
Loops
Start/End
Read/Print
Arithmetic Operations
Decision
Connectors arrows
Connectors points
Comments
Start
Read n1
N2 = 5
End
Print n1
N2 = n1+3
n1 > 3
//my name
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Simple Sequential Flow Charts
start
End
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Write a Program to Print the Sum of two integer Numbers
1. Start the program2. Read the first number and save in
the variable ( N1 )3. Read the second number and save
in the variable ( N2 )4. Sum the both numbers and save
the result in the variable ( Sum ) Sum = N1 + N2
5. Print the variable ( Sum ) 6. End the program
start
Read N1
Read N2
Sum = N1 + N2
Print Sum
End
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Write a program to print the volume of a cube and the sum of it’s surfaces’ areas
1. Start the program2. Read the length of the side and
save in variable ( Length )3. Volume = Length * Length * Length4. Surface = ( Length * Length ) * 65. Print the variable ( Volume ) 6. Print the variable ( Surface )7. End the program
start
Read L
&ٍSurface = ( L * L ) * 6
Print Volume
End
Volume = L * L * L
Print Surface
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Write a program to Print the Average of three integer numbers
start
Read num1
Read num2
result = num1+num2+num3
Print Average
End
Read num3
Average = result/3
start
Read num1,num2,num3
result = num1+num2+num3
Print Average
End
Average = result/3
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Write a program to Print the Average of three integer numbers
start
Read num1,num2,num3
Average = ( num1+num2+num3 ) / 3
Print Average
End
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Write a program to Print the Average of three integer numbers
start
Read num1
Read num2
Print Average
End
Read num3
Average = result/3
result = num1+num2+num3
start
Read num3
Read num1
result = num1+num2+num3
Print Average
End
Read num2
Average = result/3
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Write a program to Print the Average of three integer numbers
start
Read num1,num2,num3
result = num1+num2+num3
Print result
End
Average = result/3
start
Read num1,num2,num3
Print result
End
Average = result/3
result = num1+num2+num3
Print Average
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Summery
A problem-solving process for programming has five steps: analyze the problem, design an algorithm, implement the algorithm in a programming language, verify that the algorithm works, and maintain the program.
An algorithm is a step-by-step problem-solving process in which a solution is arrived at in a finite amount of time.
A flowchart is a type of diagram that represents an algorithm or process, showing the steps as boxes of various kinds, and their order by connecting them with arrows.