Why Bit Manipulation and When It Beats Arithmetic in DSA Python - Test Your Knowledge

Practice - 5 Tasks

1fill in blank

easy

Complete the code to double the number using bit manipulation.

DSA Python

result = num [1] 1

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

A<<

B>>

C+

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using right shift (>>) instead of left shift (<<).

Using arithmetic operators instead of bit shifts.

Shifting bits to the left by 1 (<< 1) multiplies the number by 2 efficiently.

2fill in blank

medium

Complete the code to check if a number is even using bit manipulation.

DSA Python

is_even = (num [1] 1) == 0

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

A|

B&

C^

D<<

Attempts:

3 left

💡 Hint

Common Mistakes

Using bitwise OR (|) instead of AND (&).

Using shift operators instead of bitwise AND.

Using bitwise AND (&) with 1 checks the least significant bit; if 0, number is even.

3fill in blank

hard

Fix the error in the code to toggle the 3rd bit of a number.

DSA Python

result = num [1] (1 << 2)

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

A>>

B|

C&

D^

Attempts:

3 left

💡 Hint

Common Mistakes

Using AND (&) which clears bits instead of toggling.

Using OR (|) which sets bits but does not toggle.

XOR (^) toggles the bit at the specified position without affecting others.

4fill in blank

hard

Fill both blanks to create a mask that clears the 4th bit of a number.

DSA Python

mask = ~(1 [1] 3)
result = num [2] mask

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

A<<

B&

C|

D^

Attempts:

3 left

💡 Hint

Common Mistakes

Using OR (|) instead of AND (&) to clear bits.

Not inverting the mask before AND operation.

Shift 1 left by 3 to target 4th bit, then invert mask and AND with number to clear that bit.

5fill in blank

hard

Fill all three blanks to extract bits 2 to 4 (inclusive) from a number.

DSA Python

mask = ((1 [1] 3) - 1) [2] (1 [3] 1)
result = (num & mask) >> 1

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

A<<

B&

C|

D>>

Attempts:

3 left

💡 Hint

Common Mistakes

Using AND (&) instead of OR (|) to combine mask parts.

Incorrect shift amounts causing wrong bits to be selected.

Shift 1 left by 3, subtract 1 to set bits 0-2, left shift by (1 | 1)=1 to position mask at bits 1-3 (0-based, i.e., 2nd-4th bits 1-based), AND extracts them, >>1 aligns to lowest bits.