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Python Python Basics Types and Branching If, Else and Elif

is there a order with elif and else ???

please ....

3 Answers

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,716 Points

Yes... there is definitely an order to this because the blocks run sequentially. You can have one "IF" condition, many "ELIF" conditions, and one "ELSE". When you have "ELIF" blocks, it is important to note that the FIRST condition that is True will run, and the rest of the blocks are skipped.

Now... because of the indentation of the code blocks, Python supports infinitely nested IF/ELIF/ELSE sttructures.

The simplest case:

if condition1:
    code block executes when condition1 is True

A typical case:

if condition1:
    code block executes when condition1 is True
else:
    code block executes when condition1 was False

A more complex case:

if condition1:
    code block executes if condition1 is True
elif condition2:
    code block executes if condition2 is True (note: if a previous condition was true, this block is skipped)
elif condition3:
    code block executes if condition3 is True (note: if a previous condition was true, this block is skipped)
else:
    code block executes if none of the above conditions were True

so is first if but only one if condition and elif is second that can have mutible condition andthen else is like if only one condition

but can if have multible lines of if and else and elif

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,716 Points

This example should explain it:

import random

# run the loop five times
for i in range(1,6):
    # get a random age between 1 and 6
    age = random.randint(1, 6)

    # print it out so we can see what the random age was
    print("-----")
    print("test # {}".format(i))
    print("Your actual age is {} years old".format(age))

    # test the age if less than or equal to three
    if age <= 3:
        print("test result: Your age is less than or equal to three.")
    else:
        print("test result: You are older than three years.")

Now... we run the program to see it work.

-----
test # 1
Your actual age is 3 years old
test result: Your age is less than or equal to three.
-----
test # 2
Your actual age is 6 years old
test result: You are older than three years.
-----
test # 3
Your actual age is 2 years old
test result: Your age is less than or equal to three.
-----
test # 4
Your actual age is 5 years old
test result: You are older than three years.
-----
test # 5
Your actual age is 5 years old
test result: You are older than three years.
Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,716 Points

Blue DiamondXD you are correct: it startes with one IF, ends with one ELSE (though this is optional), multiple ELIF conditions which are sandwiched in the middle.

This site might be helpful:

https://www.w3schools.com/python/python_conditions.asp

thank you very much one more question when your putting ang age string like if age <= 3: print ("apptional{}".format(age)) dose it alway need to be after the alse or before the else