Bit Manipulation Basics AND OR XOR NOT Left Right Shift in DSA Python - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to perform bitwise AND of two numbers.

DSA Python

result = a [1] b

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

A^

B|

C&

D~

Attempts:

3 left

💡 Hint

Common Mistakes

Using | instead of & will perform OR operation.

Using ^ will perform XOR, not AND.

The bitwise AND operator & compares each bit of two numbers and returns 1 only if both bits are 1.

2fill in blank

medium

Complete the code to perform bitwise OR of two numbers.

DSA Python

result = x [1] y

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

A^

B|

C&

D~

Attempts:

3 left

💡 Hint

Common Mistakes

Using & instead of | will perform AND operation.

Using ^ will perform XOR, not OR.

The bitwise OR operator | compares each bit of two numbers and returns 1 if at least one bit is 1.

3fill in blank

hard

Fix the error in the code to perform bitwise XOR of two numbers.

DSA Python

result = num1 [1] num2

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

A&

B|

C~

D^

Attempts:

3 left

💡 Hint

Common Mistakes

Using & or | instead of ^ will give wrong results.

Using ~ is bitwise NOT, not XOR.

The bitwise XOR operator ^ returns 1 only if the bits are different.

4fill in blank

hard

Fill both blanks to perform left shift and right shift operations.

DSA Python

left_shift = val [1] 2
right_shift = val [2] 2

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

A<<

B>>

C&

D|

Attempts:

3 left

💡 Hint

Common Mistakes

Using & or | instead of shift operators.

Mixing up left and right shift operators.

Left shift << moves bits to the left, multiplying by powers of two.
Right shift >> moves bits to the right, dividing by powers of two.

5fill in blank

hard

Fill all three blanks to create a dictionary with keys as numbers, values as bitwise NOT of keys, and filter keys greater than 2.

DSA Python

result = { [1]: [2] for [3] in range(5) if [3] > 2 }

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

Anum

B~num

Dval

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Using & or | instead of ~ for NOT operation.

We use num as the loop variable and key.
The value is bitwise NOT of num, written as ~num.
Filter keeps numbers greater than 2.

Practice

1. What is the result of the bitwise AND operation between 5 and 3? (5 = 0101, 3 = 0011 in binary)

easy

A. 1

B. 7

C. 6

D. 0

Solution

1. Step 1: Convert numbers to binary

   5 in binary is 0101, 3 in binary is 0011.

2. Step 2: Perform bitwise AND

   0101 AND 0011 = 0001 (only bits set in both numbers remain set).

3. Final Answer:

   1 -> Option A

4. Quick Check:

   5 & 3 = 1 [OK]

Hint: AND keeps bits set in both numbers only [OK]

Common Mistakes:

• Confusing AND with OR operation
• Not converting numbers to binary before operation
• Assuming decimal addition instead of bitwise AND

2. Which of the following is the correct syntax to perform a left shift by 2 bits on variable x in Python?

easy

A. x <<< 2

B. x >> 2

C. x << 2

D. x >>| 2

Solution

1. Step 1: Understand left shift operator in Python

   Left shift is done using << operator, shifting bits to the left.

2. Step 2: Check syntax options

   Only x << 2 correctly shifts bits left by 2 places.

3. Final Answer:

   x << 2 -> Option C

4. Quick Check:

   Left shift uses << operator [OK]

Hint: Use << for left shift, >> for right shift [OK]

Common Mistakes:

• Using >>> which is not valid in Python
• Confusing left shift with right shift operator
• Using invalid operators like >>|

3. What is the output of the following Python code?

num = 12  # binary 1100
result = num >> 2
print(result)

medium

A. 6

B. 0

C. 48

D. 3

Solution

1. Step 1: Convert number and apply right shift

   12 in binary is 1100. Right shifting by 2 bits removes last two bits: 1100 >> 2 = 0011.

2. Step 2: Convert shifted binary back to decimal

   0011 in binary is 3 in decimal.

3. Final Answer:

   3 -> Option D

4. Quick Check:

   12 >> 2 = 3 [OK]

Hint: Right shift divides number by 2^shift count [OK]

Common Mistakes:

• Confusing right shift with left shift
• Not converting binary back to decimal
• Assuming shift multiplies instead of divides

4. Identify the error in the following code snippet:

value = 10
result = ~value << 1
print(result)

medium

A. Result is -22 due to operator precedence

B. RuntimeError due to invalid shift

C. Result is 21 due to incorrect bitwise NOT

D. SyntaxError due to incorrect operator usage

Solution

1. Step 1: Evaluate bitwise NOT and shift

   ~10 equals -11 (because ~x = -x-1). Then shifting left by 1 bit multiplies by 2: -11 << 1 = -22.

2. Step 2: Check operator precedence and final value

   Because ~ has higher precedence, ~10 is evaluated first, then shifted. So result is -22, but print shows -22.

3. Final Answer:

   Result is -22 due to operator precedence -> Option A

4. Quick Check:

   ~10 << 1 = -22 [OK]

Hint: Bitwise NOT flips bits, watch operator precedence [OK]

Common Mistakes:

• Assuming ~10 is positive
• Ignoring operator precedence between ~ and <<
• Expecting shift to apply before NOT

5. Given two integers a = 9 and b = 14, which expression will toggle the bits where a and b differ?

hard

A. a | b

B. a ^ b

C. a & b

D. ~a

Solution

1. Step 1: Understand toggling bits where numbers differ

   Toggling bits means flipping bits that are different between two numbers.

2. Step 2: Identify bitwise XOR operation

   XOR (^) returns 1 where bits differ and 0 where bits are same, effectively toggling differing bits.

3. Final Answer:

   a ^ b -> Option B

4. Quick Check:

   XOR toggles differing bits [OK]

Hint: XOR flips bits where inputs differ [OK]

Common Mistakes:

• Using AND or OR which do not toggle bits
• Confusing NOT (~) with XOR
• Assuming OR toggles bits