Variable-length arguments (*args) in Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of function using *args with sum

What is the output of this Python code?

Python

def add_all(*args):
    return sum(args)

result = add_all(1, 2, 3, 4)
print(result)

A 10

B 1234

C TypeError

D None

💡 Hint

Remember that *args collects all arguments into a tuple and sum adds them up.

The function add_all takes any number of arguments and sums them. So 1+2+3+4 equals 10.

❓ Predict Output

intermediate

Output when *args is empty

What will this code print?

Python

def greet(*args):
    if args:
        print('Hello, ' + args[0])
    else:
        print('Hello, stranger')

greet()

A TypeError

B Hello,

C IndexError

D Hello, stranger

💡 Hint

Check what happens when no arguments are passed and how the if condition works.

Since no arguments are passed, args is empty, so the else branch runs printing 'Hello, stranger'.

❓ Predict Output

advanced

Output of function with *args and unpacking

What is the output of this code?

Python

def multiply(*args):
    result = 1
    for num in args:
        result *= num
    return result

numbers = [2, 3, 4]
print(multiply(*numbers))

A 24

B [2, 3, 4]

C 9

D TypeError

💡 Hint

The * operator unpacks the list into separate arguments.

The list [2,3,4] is unpacked into arguments 2,3,4. Multiplying them gives 2*3*4=24.

❓ Predict Output

advanced

Output when mixing *args with normal parameters

What does this code print?

Python

def describe(name, *args):
    print(f'Name: {name}')
    print(f'Other info: {args}')

describe('Alice', 25, 'Engineer')

A

Name: Alice
Other info: 25, Engineer

B

Name: Alice
Other info: (25, 'Engineer')

C

Name: Alice
Other info: [25, 'Engineer']

D TypeError

💡 Hint

Check how *args collects extra arguments as a tuple.

The first argument goes to name, the rest are collected in args as a tuple (25, 'Engineer').

🧠 Conceptual

expert

Why use *args in function definitions?

Which of these best explains why *args is used in Python functions?

A To make the function return multiple values.

B To force the function to accept exactly one argument.

C To allow the function to accept any number of positional arguments as a tuple.

D To collect keyword arguments into a dictionary.

💡 Hint

Think about how *args collects arguments.

*args collects all extra positional arguments into a tuple, allowing flexible argument counts.