Functions (reusable code blocks) in Intro to Computing - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a function named greet.

Intro to Computing

def [1]():
    print("Hello!")

Drag options to blanks, or click blank then click option'

Asay_hello

Bgreet

Chello

Dprint

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different function name than 'greet'.

Forgetting to add parentheses after the function name.

The function name should be greet to match the instruction.

2fill in blank

medium

Complete the code to call the function greet.

Intro to Computing

[1]()

Drag options to blanks, or click blank then click option'

Aprint

Bsay_hello

Chello

Dgreet

Attempts:

3 left

💡 Hint

Common Mistakes

Using print() instead of the function name.

Forgetting the parentheses after the function name.

To run the function, you write its name followed by parentheses: greet().

3fill in blank

hard

Fix the error in the function definition to accept a name parameter.

Intro to Computing

def greet([1]):
    print(f"Hello, {name}!")

Drag options to blanks, or click blank then click option'

Anames

BName

Cname

Dnam

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different parameter name than 'name'.

Capitalizing the parameter name incorrectly.

The parameter should be named name to match the variable used inside the function.

4fill in blank

hard

Fill both blanks to define and call a function that adds two numbers.

Intro to Computing

def add([1], [2]):
    return a + b

result = add(3, 4)

Drag options to blanks, or click blank then click option'

Aa

Bb

Cx

Dy

Attempts:

3 left

💡 Hint

Common Mistakes

Using parameter names that don't match the return statement.

Using more or fewer parameters than needed.

The function parameters should be a and b to match the addition inside the function.

5fill in blank

hard

Fill all three blanks to create a function that returns the square of a number and call it.

Intro to Computing

def square([1]):
    return [2] * [3]

result = square(5)

Drag options to blanks, or click blank then click option'

Anum

Dnumber

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names in the parameter and return statement.

Using a variable name not defined as a parameter.

The parameter and both operands in the return statement should be the same variable num to correctly calculate the square.

Practice

1. What is the main purpose of a function in programming?

easy

A. To display output on the screen

B. To reuse a block of code multiple times

C. To store data permanently

D. To create a new variable

Solution

1. Step 1: Understand what a function does

   A function is a reusable block of code designed to perform a specific task.

2. Step 2: Identify the main purpose

   Functions help avoid repeating the same code by allowing reuse whenever needed.

3. Final Answer:

   To reuse a block of code multiple times -> Option B

4. Quick Check:

   Function purpose = reuse code [OK]

Hint: Functions help reuse code blocks easily [OK]

Common Mistakes:

• Confusing functions with variables
• Thinking functions store data permanently
• Believing functions only display output

2. Which of the following is the correct way to define a function named greet that takes no inputs?

easy

A. function greet() {}

B. function greet:

C. def greet()

D. def greet():

Solution

1. Step 1: Recognize Python function syntax

   In Python, functions are defined using the keyword def, followed by the function name and parentheses with parameters (empty if none), ending with a colon.

2. Step 2: Check each option

   def greet(): matches Python syntax. function greet() {} and function greet: use JavaScript style or incorrect syntax. def greet() misses the colon.

3. Final Answer:

   def greet(): -> Option D

4. Quick Check:

   Python function = def name(): [OK]

Hint: Python functions start with def and end with colon [OK]

Common Mistakes:

• Omitting the colon at the end
• Using JavaScript syntax in Python
• Leaving out parentheses

3. What will be the output of this code?

def add(x, y):
    return x + y

result = add(3, 4)
print(result)

medium

A. TypeError

B. 34

C. 7

D. None

Solution

1. Step 1: Understand the function call

   The function add takes two inputs x and y and returns their sum.

2. Step 2: Calculate the return value

   Calling add(3, 4) returns 3 + 4 = 7, which is stored in result. Printing result outputs 7.

3. Final Answer:

   7 -> Option C

4. Quick Check:

   3 + 4 = 7 [OK]

Hint: Add numbers inside function returns their sum [OK]

Common Mistakes:

• Thinking it concatenates numbers as strings
• Expecting a TypeError due to missing return
• Assuming print shows None

4. Identify the error in this function definition:

def multiply(a, b)
    return a * b

medium

A. Missing colon after function header

B. Incorrect return statement

C. Function name is invalid

D. Parameters should be in square brackets

Solution

1. Step 1: Check function header syntax

   In Python, the function header must end with a colon (:). Here, it is missing after def multiply(a, b).

2. Step 2: Verify other parts

   The return statement and function name are correct. Parameters use parentheses, not square brackets.

3. Final Answer:

   Missing colon after function header -> Option A

4. Quick Check:

   Function header ends with : [OK]

Hint: Function headers always end with a colon in Python [OK]

Common Mistakes:

• Forgetting the colon at the end
• Using square brackets for parameters
• Misnaming the function

5. You want to create a function that returns the square of a number only if the number is positive; otherwise, it returns zero. Which function correctly implements this?

hard

A. def square_if_positive(n):
if n > 0:
return n * n
else:
return 0

B. def square_if_positive(n):
if n >= 0:
return n ** 2
else:
return n

C. def square_if_positive(n):
return n * n if n > 0 else None

D. def square_if_positive(n):
if n < 0:
return n * n
else:
return 0

Solution

1. Step 1: Understand the condition

   The function should return the square of n only if n is positive (greater than 0). Otherwise, it returns 0.

2. Step 2: Check each option

   def square_if_positive(n): if n > 0: return n * n else: return 0 correctly checks n > 0 and returns n * n, else 0. def square_if_positive(n): if n >= 0: return n ** 2 else: return n includes zero as positive and returns n if negative, which is incorrect. def square_if_positive(n): return n * n if n > 0 else None returns None instead of 0 when n is not positive. def square_if_positive(n): if n < 0: return n * n else: return 0 squares negative numbers and returns 0 otherwise, which is opposite.

3. Final Answer:

   def square_if_positive(n): if n > 0: return n * n else: return 0 -> Option A

4. Quick Check:

   Positive n squared, else zero [OK]

Hint: Check condition n > 0, return square else zero [OK]

Common Mistakes:

• Including zero as positive
• Returning None instead of zero
• Reversing the condition logic