1. Programming Concepts and Database
CSCI N201
Programming Concepts and Database
8 – Conditions
Lingma Acheson
Department of Computer and Information Science, IUPUI

2. Task:
Ask the user to input a required integer, and compare the input to the required integer. If it’s the same, output “You entered the right integer!” If not the same, no output.
E.g.
Comp: Please enter integer 9:
User: 9
Comp: “You entered the right integer!”

3. Algorithm Design
Pseudocode – a mixture of natural language with programming language to help in algorithm design.
Algorithm design:
- Start a new program
- Create a new variable n1
- Prompt for user input “Please enter integer 9:”
and store the input to n1
- Change n1 to integer
- If n1=9, output “You entered the right integer!”
- End the program

4. Using Miracle http://www.cs.iupui.edu/~aharris/MirJS.html
Begin the If branch (Conditional => If branch)
Give the two numbers or values to compare
Give the comparison operator
== Equals
!= Not Equal
<= Less than or equal to
>= Greater than or equal to
< Less than
> Greater than
End the If branch (Conditional => End structure)

5. If Statement Checks a condition Begins a block of code
If condition is true, executes all codes in block
If condition is false, skips code block

6. Refine the Algorithm Pseudocode: - Start a new program
- Create a new variable n1
- Prompt for user input “Please enter integer 9:”
and store the input to n1
- Change n1 to integer
- If n1==9, output “You entered the right integer!”
- End if
- End the program
Using Miracle!

7. Else Branch
If the user input is not 9, output “You entered a wrong integer!”
Pseudocode:
- Start a new program
- Create a new variable n1
- Prompt for user input “Please enter integer 9:”
and store the input to n1
- Change n1 to integer
- If n1==9
output “You entered the right integer!”
else
output “You entered a wrong integer!”
- End if
- End the program

8. Else Clause Else is a useful addition to If statements.
Else allows you to set up another block of code to execute if the condition is false
Using Miracle!

9. Lab
Create a program to compare two user inputs and output the comparison result.
Extra 20 credit:
Create a program to take two integers, ask the user to enter “+”, “-”, “*”, or “/”. Perform the correspondent maths operation and output the result to the user.