if's - selection structures

https://youtu.be/YQgFQcLOLBY

The if structure explains the processing in the following:

Input > Processing > Output

The traditional program flow.

Simple

if this then that

decisions

Syntax:

if this :

Do that

Example:

if x < 9:

print(“x is less than 9.”)

Making it useful

Ask about something you don’t know - user input:

age=input(“What is your age?”)

age=int(age)

if age>=21:

print(“Please drink responsibly.”);

print(“If you’re drinking, don’t drive.”);

print(“Have a great day!”)

It’s not: “do this or do that” - we will cover those soon

It’s: “do this or don’t do this”

But it’s best to say: “if this then do that”

which implies: “if not this, then don’t do that”