Python Control Flow (if-else, switch) Exercises

You're beginning to understand how decisions are made in Python programs. In many languages, `if`, `else`, and `switch` statements are used for control flow.

As a Python learner, which of the following statements correctly describes Python’s approach to conditional control flow?

Python supports both if-else and switch-case natively for decision-making.

Python does not support conditional logic and only supports loops for control flow.

Python uses if, elif, and else for branching logic and does not include a native switch statement.

Python uses only match-case for control flow in all versions starting from Python 2.

Python uses the if, elif, and else keywords to implement control flow and branching decisions.

Example:

x = 10
if x > 0:
    print("Positive")
elif x == 0:
    print("Zero")
else:
    print("Negative")

Unlike many other languages (like C, Java, or JavaScript), Python does not have a native switch-case structure.
However, starting from Python 3.10, a similar feature called match-case was introduced, but it’s not equivalent to traditional switch statements and has its own syntax and use cases.

For most branching needs, if-elif-else is the standard in Python, especially for versions below 3.10.

What will the following code output?

num = 7
if num < 10:
    print("Small number")

Nothing

Error

Small number

7

The value of num is 7, which is less than 10. Therefore, the condition evaluates to True, and "Small number" is printed.

Which of the following is the correct way to write an else block?

else:
  print("Done")

else
{
    print("Done")
}

else()
    print("Done")

otherwise:
  print("Done")

In Python, the correct syntax for else is:

else:
    print("Done")

The colon and indentation are essential parts of Python syntax.

Which of the following values will make the following condition true?

if x == 5:

x = 6

x = 4

x = 5

x = 0

The condition x == 5 checks if the value of x is exactly equal to 5. Only if x = 5, the condition becomes true.

What will the following code print?

x = 10
if x > 5:
    print("Greater")
else:
    print("Smaller")

Smaller

Greater

Error

Nothing

Since x is 10, and 10 is greater than 5, the condition is true and the output is "Greater". The else block will not be executed.

What will be the output of the following code?

num = 0
if num > 0:
    print("Positive")
elif num == 0:
    print("Zero")
else:
    print("Negative")

Negative

Zero

Positive

Error

The value of num is 0. The first condition (num > 0) is false. The second condition (num == 0) is true, so it prints "Zero". The else block is skipped.

Which of the following statements correctly checks if a number is either less than 10 or greater than 20?

if num < 10 and num > 20:

if num < 10 or num > 20:

if num > 10 or num < 20:

if num == 10 and num == 20:

The correct condition to check if a number is less than 10 or greater than 20 is using the or operator. It evaluates to True if either part is True.

What will the following code print if x is 4?

if x % 2 == 0:
    print("Even")
else:
    print("Odd")

Odd

Error

Even

None

The expression x % 2 calculates the remainder when x is divided by 2. If the remainder is 0, x is even. Since 4 % 2 == 0, the output is "Even".

What will be the result of this nested condition if x = 3?

if x > 0:
    if x < 5:
        print("Valid")
    else:
        print("Too big")
else:
    print("Too small")

Too big

Valid

Too small

Error

x is 3, which is greater than 0 and less than 5. So the nested condition matches and prints "Valid". The other branches are skipped.

Which of the following best describes the purpose of the elif keyword in Python?

It starts a new if statement

It replaces the else block

It adds an alternative condition between if and else

It ends the if-else block

The elif keyword is used to check multiple conditions between an if and an else. It allows branching into different execution paths based on several conditions.

What will be the output of this code?

x = 5
y = 10
if x > 0:
    if y < 5:
        print("Branch 1")
    elif y == 10:
        print("Branch 2")
    else:
        print("Branch 3")
else:
&

Branch 2

Branch 4

Branch 1

Branch 3

The outer if condition (x > 0) is true since x is 5. Inside this block, y == 10 is true, so "Branch 2" is printed.

What will this code output?

x = 8
if x % 2 == 0 and x % 4 == 0:
    print("Divisible by 4")
elif x % 2 == 0:
    print("Even")
else:
    print("Odd")

Even

Odd

Divisible by 4

None

x = 8 is divisible by both 2 and 4, so the first condition is true. Only the first matching condition is executed, so "Divisible by 4" is printed and the rest are skipped.

What will the following code print?

score = 85
if score >= 90:
    grade = 'A'
elif score >= 80:
    grade = 'B'
elif score >= 70:
    grade = 'C'
else:
    grade = 'D'
print(grade)

B

C

A

D

score is 85. The first condition (>= 90) fails. The second condition (>= 80) is true, so grade is assigned as 'B' and printed.

What will be the result of this logic?

x = 3
y = 7
if x > 2 or y < 5:
    print("True")
else:
    print("False")

False

True

Error

None

x > 2 is true (3 > 2). The or operator returns True if any condition is true, so "True" is printed regardless of y’s value.

Which of these is the best way to simulate switch-case in Python?

Using nested if-else statements

Using a for loop

Using a dictionary mapping

Using while loop

Python does not have a native switch-case statement. A common alternative is to use a dictionary to map values to functions or outputs. For example:

def case1(): return "One"
def case2(): return "Two"
choices = {1: case1, 2: case2}
print(choices.get(1, lambda: "Default")())

What will be printed by the following code?

x = 0
if x:
    print("True block")
else:
    print("False block")

True block

False block

x

0

In Python, the value 0 is considered False in a Boolean context. So the condition if x: is not satisfied, and the else block is executed.

Which of the following conditions will be considered False by Python?

if " "

if []

if [1, 2]

if "Python"

Empty data structures like empty lists ([]), dictionaries ({}), and strings ("") are considered False in Python. Non-empty ones are True. So only if [] is False.

What is the output of this code?

a = 5
b = 10
if a > 2:
    if b < 15:
        print("A")
else:
        print("B")
print("C")

A

A C

B C

C

Both conditions are true: a > 2 and b < 15. So "A" is printed. After the if-else blocks, "C" is printed unconditionally.

Which of the following values will make this condition false?

if x:

x = -1

x = 0

x = 100

x = "hello"

In a Boolean context, only certain values are considered False in Python: 0, 0.0, False, None, '', [], {}, etc. Here, only x = 0 makes the condition false.

Which of the following is NOT a valid Python way to use an if-else expression?

print("Yes") if x > 0 else print("No")

if x > 0 then print("Yes")

if x > 0:
    print("Yes")
else:
    print("No")

y = 10 if x > 5 else 5

Python does not use then in conditional syntax. That’s used in other languages like Pascal or BASIC. The correct syntax is if condition:

Python Control Flow (if-else, switch) Exercises

You're beginning to understand how decisions are made in Python programs. In many languages, if, else, and switch statements are used for control flow.

As a Python learner, which of the following statements correctly describes Python’s approach to conditional control flow?

What will the following code output?

Which of the following is the correct way to write an else block?

Which of the following values will make the following condition true?

What will the following code print?

What will be the output of the following code?

Which of the following statements correctly checks if a number is either less than 10 or greater than 20?

What will the following code print if x is 4?

What will be the result of this nested condition if x = 3?

Which of the following best describes the purpose of the elif keyword in Python?

What will be the output of this code?

What will this code output?

What will the following code print?

What will be the result of this logic?

Which of these is the best way to simulate switch-case in Python?

What will be printed by the following code?

Which of the following conditions will be considered False by Python?

What is the output of this code?

Which of the following values will make this condition false?

Which of the following is NOT a valid Python way to use an if-else expression?

About This Exercise: Python – Control Flow (if-else, switch)

You're beginning to understand how decisions are made in Python programs. In many languages, `if`, `else`, and `switch` statements are used for control flow.