Transcript num3 - missn

ICS 3U
Friday, September 10
Pseudocode Practice #1
Average of 3 numbers inputted from the user.
1.
2.
3.
4.
5.
6.
7.
8.
9.
Ask the user to input a number.
Store as num1.
Ask the user to input a number.
Store as num2.
Ask the user to input a number.
Store as num3.
total = num1 + num2 + num3
average = total / 3
Output the average
Pseudocode Practice #2
Sort 3 Numbers (none are equal)
1.
2.
3.
Ask the user to input a number and store in num1
Repeat step one for num2 and num3 (output, input, store)
If num1 > num2 and num1 > num3 then
a.
b.
4.
Else, if num2 > num1 and num2 > num3 then
a.
b.
5.
If num2 > num3 then
i.
Output num1, num2, num3 (sorted order)
Otherwise then
i.
Output num1, num3, num2
If num1 > num3 then
i.
Output num2, num1, num3
Otherwise then
i.
Output num2, num3, num1
Otherwise (num3 is the largest)
a.
b.
If num1 > num2 then
i.
Output num3, num1, num2
Otherwise
i.
Output num3, num2, num1
I – P – O Model
Input - state the input provided/needed
Processing


writing an algorithm
specifying the method needed to solve the
problem (instructions, pseudocode).
Output - state the final output of the
problem
How Computers Solve Problems
People use computers to help them solve “problems”.
These “problems” could range from word processing a
letter, creating a web page, doing a scientific space
simulation, communicating with friends, or playing a game.
Input – user specifies input using an input device (mouse,
keyboard)
Processing – Computer’s processor runs a computer
program that processes the input data, and through a
series of logical comparisons and calculations, solve the
problem
Output – computer outputs the solution using an output
device (monitor, speakers, printer)
I-P-O Computer Example

Creating a Resume
Input – User types text on a keyboard, uses the mouse to
choose formatting options from menus, etc.
Processing – The computer processes the user’s requests
and responds accordingly (ie. when the user presses tab,
the computer inserts spaces in the text).
Output – The computer displays the resume on the monitor.
The user can also choose to output it to a printer.
Problem Solving Example
Example: Convert a mark on a test to a percent.
Inputs:


mark earned
total possible marks (out of)
Processing
1.
2.
divide the mark earned by the total possible marks
Multiply by 100
Output

Student mark as a percent
I-P-O Model Practice
Take the following problems through a
complete I-P-O Model. (Just write
instructions for the processing part).
1.
Divide a pizza order amount a group of
friends.
2.
Calculate the amount of change for a
purchase (include determining the
amount of each denomination).
Brainstorming Activity

Brainstorm about what makes a good
program.


From the user’s perspective
From the programmer’s perspective