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Getting started

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Selection

Selection happens all the time in games, apps and programs. Human being love to have choices, so if you are coding you should use "selection" to provide them.
Here is a simple program that has selection. The important Python syntax (or keyword) for selection is "if" and "else".
Picture
age = 21
if age >= 18:
   print ("Adult")
else:
   print ("Child") 

Write this code below and test it out. Here are some common mistakes:
  1. You forgot a colon (:)
  2. One of the lines is not indented
  3. You forgot a speech mark
  4. You forgot a "greater than" sign (or put the wrong sign)
​    
Did it work? Make the following changes and then see what happens:
  • Change the value held in the variable from 21 to 16
  • Change the string "Adult" to anything else (keep the speech marks)
  • Change the string "child" to anything else (keep the speech marks)

Code something with selection

Use the example code in task  above. Can you create some code that does the following?

  • A variable called “age” should be declared that contains the value 22.
  • Using selection (if/else), the code should display “You are old enough to drive” after it has been run.
  • However, if the value in the variable called “age” is changed to 15, the code should display “You are NOT old enough to drive”
  • NOTE: You must be 16 or older to drive in the UK.

Fix this code

This selection code below is in the wrong order, can you fix it?

print("welcome to the Club")
print("Sorry, you're not old enough to join yet")
age = int(input("please enter your age "))
else
if age >= 14 

Get it working in the code editor below.
Don't forget the indentation-------->
Goodluck!
Picture

Test you knowledge

Loading KS3 – Python – Selection
Loading KS3 - Comparison operators
< inputs
Flowcharts >
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