[Python Puzzle Rush] Do You Understand Python Loops? ?

This article gives you five code puzzles to help you master basic looping in Python.

• If you are a Python expert, you solve all of them without even the slightest mistake.
• If you are a Python intermediate, you make one or two mistakes.
• If you are a Python beginner, you should get at least one right.

Have a look at your clock: 5-minutes starting now… Go, go, go!

Puzzle 1: While Loop Changing Values Dynamically

The while loop can be used to repeat a certain behavior until a variable meets a certain condition.

n = 16
x = 0

while x < 3:
    n /= 2
    x += 1
    
print(n)

What’s the output of this code snippet?

Solve the puzzle on the interactive puzzle app (Finxter.com website).

Puzzle 2: Lambda Function and Range

This puzzle tests your understanding of two concepts: the lambda function and the built-in range() function.

inc = lambda x: x + 1
for i in range(2, 3):
    print(inc(2))

What’s the output of this code snippet?

Solve the puzzle on the interactive puzzle app (Finxter.com website).

Puzzle 3: While … Else Branch

Next, you’ll explore a strange Python feature: the else branch … of a while loop!

index = 5
string = 'g'

while index > 3:
    index -= 1
    string += 'o'
else:
    string += 'd'

print(string)

What’s the output of this code snippet?

Solve the puzzle on the interactive puzzle app (Finxter.com website).

Puzzle 4: While … Else Branch 2

index = 5
string = 'g'

while index > 3:
    index -= 1
    string += 'o'
    if index == 3:
        break
else:
    string += 'd'

print(string)

What’s the output of this code snippet?

Solve the puzzle on the interactive puzzle app (Finxter.com website).

Puzzle 5: While … Else Branch 3

index = 5
string = 'g'

while index > 3:
    index -= 1
    if index == 3:
        continue
    string += 'o'

else:
    string += 'd'

print(string)

What’s the output of this code snippet?

Solve the puzzle on the interactive puzzle app (Finxter.com website).

Solutions

How many puzzles have you solved correctly? Here are the correct solutions:

• Puzzle 1: 2.0
• Puzzle 2: 3
• Puzzle 3: good
• Puzzle 4: goo
• Puzzle 5: god

If you have solved at least four puzzles correctly, you belong to the top 20% of Python coders.

Related Video: Loop … Else

Do you want to master even advanced concepts of Python loops? Watch my short explainer video on the meaning of the else branch of a Python loop.

A Surprising Python Trick: Loop ... Else?!

You can solve more puzzles and download your Python cheat sheets in my free email academy: