Check if Number is Power of Two in DSA Python - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if a number is a power of two using bitwise AND.

DSA Python

def is_power_of_two(n):
    return n > 0 and (n & ([1])) == 0

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

An - 1

Bn + 1

C1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using n + 1 instead of n - 1

Checking n & 1 which only checks if n is odd

Using 0 instead of n - 1 in the bitwise AND

The expression n & (n - 1) clears the lowest set bit. For powers of two, this results in zero.

2fill in blank

medium

Complete the code to return False immediately if the number is not positive.

DSA Python

def is_power_of_two(n):
    if [1]:
        return False
    return (n & (n - 1)) == 0

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

An == 0

Bn <= 0

Cn < 0

Dn >= 0

Attempts:

3 left

💡 Hint

Common Mistakes

Checking only for n == 0 and missing negative numbers

Using n >= 0 which includes zero and positive numbers

Only positive numbers can be powers of two, so return False if n is zero or negative.

3fill in blank

hard

Fix the error in the code to correctly check if n is a power of two.

DSA Python

def is_power_of_two(n):
    if n <= 0:
        return False
    return (n & ([1])) == 0

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

An - 1

Bn + 1

C1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using n + 1 instead of n - 1

Using 1 or 0 directly in the bitwise AND

The correct expression is n & (n - 1) to check if n is a power of two.

4fill in blank

hard

Fill both blanks to complete the function that returns True if n is a power of two, else False.

DSA Python

def is_power_of_two(n):
    if n [1] 0:
        return False
    return (n & (n [2] 1)) == 0

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

A<=

B>

C-

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using > 0 instead of <= 0 in the if condition

Using + 1 instead of - 1 in the bitwise AND

Check if n is less than or equal to zero to return False. Then use n - 1 in the bitwise AND.

5fill in blank

hard

Fill all three blanks to complete the function that checks if a number is a power of two.

DSA Python

def is_power_of_two(n):
    if n [1] 0:
        return False
    return (n [2] (n [3] 1)) == 0

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

A<=

B&

C-

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using + instead of - in the expression

Using | instead of & for bitwise operation

Checking n < 0 instead of n <= 0

Return False if n is less than or equal to zero. Then use bitwise AND (&) between n and n - 1.