Coding interview preparation
5.75K subscribers
330 photos
47 files
163 links
Download Telegram
How Redis Architecture Evolves?
๐Ÿ”’๐Ÿ’ป 27 Free Resources to Learn Ethical Hacking! ๐Ÿ’ป๐Ÿ”’

๐Ÿš€ Dive into the world of ethical hacking with these handpicked resources:

Root Me โ€” Challenges
Stรถk's YouTube โ€” Videos
Hacker101 Videos โ€” Videos
InsiderPhD YouTube โ€” Videos
EchoCTF โ€” Interactive Learning
Vuln Machines โ€” Videos and Labs
Try2Hack โ€” Interactive Learning
Pentester Land โ€” Written Content
Checkmarx โ€” Interactive Learning
Cybrary โ€” Written Content and Labs
RangeForce โ€” Interactive Exercises
Vuln Hub โ€” Written Content and Labs
TCM Security โ€” Interactive Learning
HackXpert โ€” Written Content and Labs
Try Hack Me โ€” Written Content and Labs
OverTheWire โ€” Written Content and Labs
Hack The Box โ€” Written Content and Labs
CyberSecLabs โ€” Written Content and Labs
Pentester Academy โ€” Written Content and Labs
Bug Bounty Reports Explained YouTube โ€” Videos
Web Security Academy โ€” Written Content and Labs
Securibee's Infosec Resources โ€” Written Content
Jhaddix Bug Bounty Repository โ€” Written Content
Zseano's Free Bug Bounty Methodology โ€” Free Ebook
Awesome AppSec GitHub Repository โ€” Written Content
NahamSec's Bug Bounty Beginner Repository โ€” Written Content
Kontra Application Security Training โ€” Interactive Learning

๐Ÿ’ก From beginners to pros, these resources offer a plethora of knowledge and hands-on experience to sharpen your ethical hacking skills.

#EthicalHacking #CyberSecurity
โž–โž–โž–โž–โž–โž–โž–โž–โž–โž–โž–โž–โž–โž–
Join @coding_interview_preparation for more interview questions.
*This channel belongs to @bigdataspecialist group
bug , setTime out is asynchronous
Well Known TCP/UDP Ports
Apple pay and Google pay Security
CI/CD Workflow
What is an OSI model
Database keys

Database keys are essential for organizing and managing data effectively. In this post, we'll explore ten key concepts that every IT professional should know.

1. ๐Ÿ— ๐—ฃ๐—ฟ๐—ถ๐—บ๐—ฎ๐—ฟ๐˜† ๐—ž๐—ฒ๐˜†
- A unique identifier for each record in a table.
- Cannot be null.
- Ensures that each row is unique.

2. ๐ŸŒ‰ ๐—™๐—ผ๐—ฟ๐—ฒ๐—ถ๐—ด๐—ป ๐—ž๐—ฒ๐˜†
- A field in one table that refers to the Primary Key of another table.
- Establishes relationships between tables.

3. ๐Ÿงฉ ๐—–๐—ผ๐—บ๐—ฝ๐—ผ๐˜€๐—ถ๐˜๐—ฒ ๐—ž๐—ฒ๐˜†
- A combination of two or more columns that uniquely identifies each record.
- Useful when a single column can't uniquely identify a record.

4. ๐Ÿ’ช ๐—ฆ๐˜‚๐—ฝ๐—ฒ๐—ฟ ๐—ž๐—ฒ๐˜†
- One or more columns that can uniquely identify a record.
- A Primary Key is a type of Super Key.

5. ๐Ÿ… ๐—–๐—ฎ๐—ป๐—ฑ๐—ถ๐—ฑ๐—ฎ๐˜๐—ฒ ๐—ž๐—ฒ๐˜†
- A column or set of columns that could be the Primary Key.
- Must be unique.

6. ๐Ÿ” ๐—จ๐—ป๐—ถ๐—พ๐˜‚๐—ฒ ๐—ž๐—ฒ๐˜†
- Ensures uniqueness for a column or column combination.
- Similar to Primary Key but allows one null value.

7. ๐Ÿ›ค ๐—”๐—น๐˜๐—ฒ๐—ฟ๐—ป๐—ฎ๐˜๐—ฒ ๐—ž๐—ฒ๐˜†
- A Candidate Key that isn't the Primary Key.
- Another option for a unique identifier.

8. ๐Ÿƒ ๐—ก๐—ฎ๐˜๐˜‚๐—ฟ๐—ฎ๐—น ๐—ž๐—ฒ๐˜†
- A key that's a natural part of the data, like an email address.

9. ๐ŸŽญ ๐—ฆ๐˜‚๐—ฟ๐—ฟ๐—ผ๐—ด๐—ฎ๐˜๐—ฒ ๐—ž๐—ฒ๐˜†
- An artificial key created when no natural unique identifier exists.

10. ๐Ÿ”‘ ๐—ฆ๐—ฒ๐—ฐ๐—ผ๐—ป๐—ฑ๐—ฎ๐—ฟ๐˜† ๐—ž๐—ฒ๐˜†
- Used for data retrieval, not identification.
- Helps create non-clustered indexes.
Syntax Error!!!

Cause you can't declare the same variable two times. The variable num is declared twice within the same scope: once using var and then using let. Redeclaring a variable with let or const in the same scope is not allowed, leading to a syntax error.
+ operator will first convert the string to a numeric value.
so "0" -> 0
after that, it's post incrementing, so it will not increment
thus output will remain 0

P.S : There are two types of increment (post & pre)

Post (a++) will print first then increment
Pre (++a) will increment first then print
Cyber Security Courses
Forward Proxy vs Reverse Proxy
PC Components
System Design Cheat Sheet
100+ Practice Questions

โ C/C++
โ Python
โ JavaScript
โ Java
โ C#
โ Golang

โžŠ Simple Numbers

โž€ Find a digit at a specific place in a number
โž Find count of digits in a number
โž‚ Find the largest digit
โžƒ Find the 2nd largest digit
โž„ Find the kth largest digit
โž… Find the smallest digit
โž† Find the 2nd smallest digit
โž‡ Find the kth smallest digit
โžˆ Find generic root (sum of all digits) of a number
โž‰ Reverse the digits in a number
โž€โž€ Rotate the digits in a number
โž€โž Is the number a palindrome?
โž€โž‚ Find sum of 'n' numbers
โž€โžƒ Check if a number is perfect square
โž€โž„ Find a number in an AP sequence
โž€โž… Find a number in a GP sequence
โž€โž† Find a number in fibonacci sequence
โž€โž‡ Check number divisibility by 2, 3, 5, 9
โž€โžˆ Check if a number is primary or not
20. Given a number, print all primes smaller than it
โžโž€ Check if a number is circular prime or not
โžโž Find all prime factors of a number
โžโž‚ Find the GCD of 2 numbers
โžโžƒ Find the LCM of 2 numbers
โžโž„ Find the factorial of a number
โžโž… Find the exponentiation of a number

โž‹ Unit Conversion

โž€ Number Base (Binary, Octal, Hexadecimal, Decimal)
โž Weight (gram, kg, pound)
โž‚ Height (cm, m, inch, feet)
โžƒ Temperature (centigrade, fahrenhite)
โž„ Distance (km, mile)
โž… Area (mยฒ, kmยฒ, acre)
โž† Volume (ltr, gallon)
โž‡ Time (sec, min, hour)
โžˆ Currency

โžŒ Calculator

โž€ Loan EMI Calculator
โž Fixed Deposit Returns Calculator
โž‚ Interest Calculator
โžƒ BMI Calculator
โž„ Item Price (considering tax, discount, shipping)
โž… Tip Calculator

โž Geometry

โž€ Find distance between 2 points
โž Given 2 sides of a right angle triangle, find the 3rd
โž‚ Find 3rd angle of a triangle when 2 are given
โžƒ Area of a triangle when 3 sides are given
โž„ Area of a right angle triangle
โž… Perimeter of a Square
โž† Area of a Square
โž‡ Perimeter of a Rectangle
โžˆ Area of a Rectangle
โž‰ Circumference of a Circle
โž€โž€ Area of a Circle
โž€โž Circumference of a Semi-Circle
โž€โž‚ Area of a Semi-Circle
โž€โžƒ Area of a Ring
โž€โž„ Circumference of an Ellipse
โž€โž… Area of an Ellipse
โž€โž† Suface Area of a Sphere
โž€โž‡ Volume of a Sphere
โž€โžˆ Surface Area of a Hemisphere
20. Volume of a Hemisphere
โžโž€ Surface area of a Cube
โžโž Volume of a Cube
โžโž‚ Surface area of a Cylinder
โžโžƒ Volume of a Cylinder

โžŽ Vector

โž€ Find Scalar Multiplication of a vector
โž Find addition/subtraction of vectors
โž‚ Find magnitude of a vector
โžƒ Find an unit vector along a given vector
โž„ Find dot product of 2 vectors
โž… Find cross product of 2 vectors
โž† Check if 2 vectors are orthogonal

โž Matrix

โž€ Find the determinant of a matrix
โž Find Scalar Multiplication of a matrix
โž‚ Find addition/subtraction of matrices
โžƒ Find the transpose of a matrix
โž„ Find if 2 matrices are orthogonal
โž… Find inverse of a 2x2 and 3x3 matrix

โž Set

โž€ Find Union of 2 sets
โž Find Intersection of 2 sets
โž‚ Find the Difference of 2 sets
โžƒ Find the Symmetric Difference of 2 sets
โž„ Find if a set is subset/superset of another set
โž… Find if 2 sets are disjoints

โž‘ Special Numbers

โž€ Strong Number
โž Perfect Number
โž‚ Armstrong Number
โžƒ Harshad Number
โž„ Kaprekar Number
โž… Lychrel Number
โž† Narcissistic Decimal Number
โž‡ Lucus Number
โžˆ Catalan Number
โž‰ Duck Number
โž€โž€ Ugly Number
โž€โž Abundant Number
โž€โž‚ Deficient Number
โž€โžƒ Automorphic Number
โž€โž„ Magic Number
โž€โž… Friendly Pair Numbers
โž€โž† Neon Number
โž€โž‡ Spy Number
โž€โžˆ Happy Number
20. Sunny Number
โžโž€ Disarium Number
โžโž Pronic Number
โžโž‚ Trimorphic Number
โžโžƒ Evil Number
โžโž„ Amicable Pairs

๐Ÿšฅ Last Words

โฌ˜ If you want to excel in programming, practice a lot.

โฌ™ Problems based on numbers are easy to start with and they help in improving your analytical skills.
Roadmap to Java Programming
OSI Model vs Protocols
SQL commands you should know
Types of Shell in Linux
Important Docker Commands
Network Protocols