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Top 5 Coding Challenge Platforms for Programmers ๐Ÿ‘ฉโ€๐Ÿ’ป๐Ÿš€

1. LeetCode
   - URL: https://leetcode.com
   - Description: Enhance problem-solving skills with a vast collection of coding challenges on LeetCode.

2. HackerRank
   - URL: https://www.hackerrank.com
   - Description: HackerRank offers diverse coding challenges for algorithm, data structure, and language proficiency improvement.

3. CodeSignal
   - URL: https://codesignal.com
   - Description: CodeSignal provides coding challenges and assessments to enhance coding skills for interviews and practice.

4. Codewars

   - URL: https://www.codewars.com
   - Description: Codewars engages developers in creative problem-solving through kata challenges, fostering skill development.

5. Exercism
   - URL: https://exercism.io
   - Description: Exercism offers coding exercises in various languages, providing mentorship and community support.

โžก๏ธ Give Reactions ๐ŸคŸ
Top 5 Coding Challenge Platforms for Programmers ๐Ÿ‘ฉโ€๐Ÿ’ป๐Ÿš€

1. LeetCode
   - URL: https://leetcode.com
   - Description: Enhance problem-solving skills with a vast collection of coding challenges on LeetCode.

2. HackerRank
   - URL: https://www.hackerrank.com
   - Description: HackerRank offers diverse coding challenges for algorithm, data structure, and language proficiency improvement.

3. CodeSignal
   - URL: https://codesignal.com
   - Description: CodeSignal provides coding challenges and assessments to enhance coding skills for interviews and practice.

4. Codewars
   - URL: https://www.codewars.com
   - Description: Codewars engages developers in creative problem-solving through kata challenges, fostering skill development.

5. Exercism
   - URL: https://exercism.io
   - Description: Exercism offers coding exercises in various languages, providing mentorship and community support.
Answer: No

As we have 2 == operators, so they are executed from left to right.

a == b == c
โ‡’ (a == b) == c
โ‡’ (10 == 10) == 10
โ‡’ true == 10
โ‡’ 1 == 10
โ‡’ false

Why is true converted to 1?
The rule for == says if one of the operands is boolean, it's converted to number before the comparison.
true is converted to its number value, which is 1.
Dear Community,

It's become challenging to balance content creation alongside my full-time job and creation of app that will give you any course for free - I am working on that after work for previous 8 months).
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Warm regards,
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18 Most common used Java List methods

1. add(E element) - Adds the specified element to the end of the list.
2. addAll(Collection<? extends E> c) - Adds all elements of the specified collection to the end of the list.
3. remove(Object o) - Removes the first occurrence of the specified element from the list.
4. remove(int index) - Removes the element at the specified position in the list.
5. get(int index) - Returns the element at the specified position in the list.
6. set(int index, E element) - Replaces the element at the specified position in the list with the specified element.
7. indexOf(Object o) - Returns the index of the first occurrence of the specified element in the list.
8. contains(Object o) - Returns true if the list contains the specified element.
9. size() - Returns the number of elements in the list.
10. isEmpty() - Returns true if the list contains no elements.
11. clear() - Removes all elements from the list.
12. toArray() - Returns an array containing all the elements in the list.
13. subList(int fromIndex, int toIndex) - Returns a view of the portion of the list between the specified fromIndex, inclusive, and toIndex, exclusive.
14. addAll(int index, Collection<? extends E> c) - Inserts all elements of the specified collection into the list, starting at the specified position.
15. iterator() - Returns an iterator over the elements in the list.
16. sort(Comparator<? super E> c) - Sorts the elements of the list according to the specified comparator.
17. replaceAll(UnaryOperator<E> operator) - Replaces each element of the list with the result of applying the given operator.
18. forEach(Consumer<? super E> action) - Performs the given action for each element of the list until all elements have been processed or the action throws an exception.
Common Programming Interview Questions

How do you reverse a string?
How do you determine if a string is a palindrome?
How do you calculate the number of numerical digits in a string?
How do you find the count for the occurrence of a particular character in a string?
How do you find the non-matching characters in a string?
How do you find out if the two given strings are anagrams?
How do you calculate the number of vowels and consonants in a string?
How do you total all of the matching integer elements in an array?
How do you reverse an array?
How do you find the maximum element in an array?
How do you sort an array of integers in ascending order?
How do you print a Fibonacci sequence using recursion?
How do you calculate the sum of two integers?
How do you find the average of numbers in a list?
How do you check if an integer is even or odd?
How do you find the middle element of a linked list?
How do you remove a loop in a linked list?
How do you merge two sorted linked lists?
How do you implement binary search to find an element in a sorted array?
How do you print a binary tree in vertical order?

Conceptual Coding Interview Questions

What is a data structure?
What is an array?
What is a linked list?
What is the difference between an array and a linked list?
What is LIFO?
What is FIFO?
What is a stack?
What are binary trees?
What are binary search trees?
What is object-oriented programming?
What is the purpose of a loop in programming?
What is a conditional statement?
What is debugging?
What is recursion?
What are the differences between linear and non-linear data structures?


General Coding Interview Questions

What programming languages do you have experience working with?
Describe a time you faced a challenge in a project you were working on and how you overcame it.
Walk me through a project youโ€™re currently or have recently worked on.
Give an example of a project you worked on where you had to learn a new programming language or technology. How did you go about learning it?
How do you ensure your code is readable by other developers?
What are your interests outside of programming?
How do you keep your skills sharp and up to date?
How do you collaborate on projects with non-technical team members?
Tell me about a time when you had to explain a complex technical concept to a non-technical team member.
How do you get started on a new coding project?
How Redis Architecture Evolves?
๐Ÿ”’๐Ÿ’ป 27 Free Resources to Learn Ethical Hacking! ๐Ÿ’ป๐Ÿ”’

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Join @coding_interview_preparation for more interview questions.
*This channel belongs to @bigdataspecialist group
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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
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