Bit Manipulation Basics AND OR XOR NOT Left Right Shift in DSA Typescript - Build from Scratch

Bit Manipulation Basics AND OR XOR NOT Left Right Shift

📖 Scenario: Imagine you are working with a simple device that stores settings as numbers. Each bit in the number represents a different setting that can be turned ON or OFF. You want to learn how to change these settings using bit operations.

🎯 Goal: You will create a TypeScript program that uses bit manipulation operators: AND, OR, XOR, NOT, left shift, and right shift to change and check settings represented by numbers.

📋 What You'll Learn

Create variables with exact numbers for settings

Use bitwise AND, OR, XOR, NOT operators with given variables

Use left shift and right shift operators with given numbers

Print the results exactly as specified

💡 Why This Matters

🌍 Real World

Bit manipulation is used in low-level programming, device control, and performance optimization where settings or flags are stored as bits.

💼 Career

Understanding bitwise operations is important for roles in embedded systems, game development, and systems programming.

1

Create initial settings variables

Create two variables called settingA and settingB with values 5 and 3 respectively.

DSA Typescript

// Your code here
// Create settingA and settingB variables

Hint

Use const to create variables and assign the exact numbers 5 and 3.

2

Create a variable for left shift amount

Create a variable called shiftAmount and set it to 1.

DSA Typescript

const settingA = 5;
const settingB = 3;
// Your code here
// Create shiftAmount variable

Hint

Use const shiftAmount = 1; to create the variable.

3

Apply bitwise operations

Create variables andResult, orResult, xorResult, notResult, leftShiftResult, and rightShiftResult. Set them to the results of applying bitwise AND, OR, XOR between settingA and settingB, bitwise NOT of settingA, left shift settingA by shiftAmount, and right shift settingA by shiftAmount respectively.

DSA Typescript

const settingA = 5;
const settingB = 3;
const shiftAmount = 1;
// Your code here
// Create andResult, orResult, xorResult, notResult, leftShiftResult, rightShiftResult

Hint

Use the bitwise operators &, |, ^, ~, <<, and >> with the variables as described.

4

Print all results

Print the values of andResult, orResult, xorResult, notResult, leftShiftResult, and rightShiftResult each on a new line in this exact order.

DSA Typescript

const settingA = 5;
const settingB = 3;
const shiftAmount = 1;

const andResult = settingA & settingB;
const orResult = settingA | settingB;
const xorResult = settingA ^ settingB;
const notResult = ~settingA;
const leftShiftResult = settingA > shiftAmount;
// Your code here
// Print all results in order

Hint

Use console.log() to print each variable on its own line in the order given.

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 operation

   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 operation

2. Which of the following is the correct TypeScript syntax to perform a bitwise XOR between variables a and b?

easy

A. let result = a && b;

B. let result = a % b;

C. let result = a | b;

D. let result = a ^ b;

Solution

1. Step 1: Identify bitwise XOR operator in TypeScript

   The bitwise XOR operator is the caret symbol (^).

2. Step 2: Check each option for correct syntax

   let result = a ^ b; uses ^ correctly. let result = a && b; uses logical AND (&&), let result = a | b; uses bitwise OR (|), let result = a % b; uses modulus (%).

3. Final Answer:

   let result = a ^ b; -> Option D

4. Quick Check:

   Bitwise XOR uses ^ operator [OK]

Hint: XOR operator is ^ in TypeScript [OK]

Common Mistakes:

• Using logical operators instead of bitwise
• Confusing OR (|) with XOR (^)
• Using modulus operator (%) by mistake

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

const x = 8; // binary 1000
const y = x >> 2;
console.log(y);

medium

A. 0

B. 2

C. 1

D. 4

Solution

1. Step 1: Understand right shift operation

   Right shift (>>) moves bits to the right by the specified number, dropping rightmost bits.

2. Step 2: Apply right shift to 8 (1000 binary)

   Shifting 1000 right by 2 bits gives 0010 binary, which is 2 in decimal.

3. Final Answer:

   2 -> Option B

4. Quick Check:

   8 >> 2 = 2 [OK]

Hint: Right shift divides by 2 for each shift [OK]

Common Mistakes:

• Confusing right shift with left shift
• Not converting binary to decimal after shift
• Assuming shift adds zeros on left without dropping bits

4. Identify the error in this TypeScript code snippet:

let a = 5;
let b = 3;
let c = a <<< b;
console.log(c);

medium

A. <<< is not a valid bitwise operator

B. Variables a and b must be strings

C. Missing semicolon after variable declarations

D. Bitwise operators cannot be used with let variables

Solution

1. Step 1: Check the bitwise operators in TypeScript

   Valid bitwise shift operators are << (left shift) and >> (right shift). There is no <<< operator.

2. Step 2: Identify the invalid operator usage

   The code uses <<< which is invalid syntax and will cause an error.

3. Final Answer:

   <<< is not a valid bitwise operator -> Option A

4. Quick Check:

   Only << and >> are valid shift operators [OK]

Hint: Use only << or >> for shifts, not <<< or >>> [OK]

Common Mistakes:

• Using triple shift operator like in some other languages
• Assuming semicolons are mandatory for correctness
• Thinking bitwise operators require specific variable types

5. Given n = 29 (binary 11101), which expression will toggle the 3rd bit (counting from 0 at right) using bitwise XOR in TypeScript?
Choose the correct code snippet.

hard

A. let result = n | (1 << 3);

B. let result = n & (1 << 3);

C. let result = n ^ (1 << 3);

D. let result = ~n ^ (1 << 3);

Solution

1. Step 1: Understand toggling a bit with XOR

   XOR with 1 flips the bit; XOR with 0 leaves it unchanged.

2. Step 2: Create mask for 3rd bit

   1 << 3 shifts 1 to the 3rd bit position (binary 1000).

3. Step 3: Apply XOR to toggle the bit

   n ^ (1 << 3) flips the 3rd bit of n.

4. Final Answer:

   let result = n ^ (1 << 3); -> Option C

5. Quick Check:

   XOR with mask toggles bit [OK]

Hint: XOR with 1 at bit toggles it, 0 leaves it same [OK]

Common Mistakes:

• Using AND or OR instead of XOR to toggle bits
• Incorrect bit position shift
• Using NOT operator incorrectly with XOR