Coding Interview Resources
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This channel contains the free resources and solution of coding problems which are usually asked in the interviews.

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When youโ€™re in an interview, itโ€™s super important to know how to talk about your projects in a way that impresses the interviewer. Here are some key points to help you do just that:

โžค ๐—ฃ๐—ฟ๐—ผ๐—ท๐—ฒ๐—ฐ๐˜ ๐—ข๐˜ƒ๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ฒ๐˜„:
- Start with a quick summary of the project you worked on. What was it all about? What were the main goals? Keep it short and sweet something you can explain in about 30 seconds.

โžค ๐—ฃ๐—ฟ๐—ผ๐—ฏ๐—น๐—ฒ๐—บ ๐—ฆ๐˜๐—ฎ๐˜๐—ฒ๐—บ๐—ฒ๐—ป๐˜:
- What problem were you trying to solve with this project? Explain why this problem was important and needed addressing.

โžค ๐—ฃ๐—ฟ๐—ผ๐—ฝ๐—ผ๐˜€๐—ฒ๐—ฑ ๐—ฆ๐—ผ๐—น๐˜‚๐˜๐—ถ๐—ผ๐—ป:
- Describe the solution you came up with. How does it work, and why is it a good fix for the problem?

โžค ๐—ฌ๐—ผ๐˜‚๐—ฟ ๐—ฅ๐—ผ๐—น๐—ฒ:
- Talk about what you specifically did. What were your main tasks? Did you face any challenges, and how did you overcome them? Make sure itโ€™s clear whether you were leading the project, a key player, or supporting the team.

โžค ๐—ง๐—ฒ๐—ฐ๐—ต๐—ป๐—ผ๐—น๐—ผ๐—ด๐—ถ๐—ฒ๐˜€ ๐—ฎ๐—ป๐—ฑ ๐—ง๐—ผ๐—ผ๐—น๐˜€:
- Mention the tech and tools you used. This shows your technical know-how and your ability to choose the right tools for the job.

โžค ๐—œ๐—บ๐—ฝ๐—ฎ๐—ฐ๐˜ ๐—ฎ๐—ป๐—ฑ ๐—”๐—ฐ๐—ต๐—ถ๐—ฒ๐˜ƒ๐—ฒ๐—บ๐—ฒ๐—ป๐˜๐˜€:
- Share the results of your project. Did it make things better? How? Mention any improvements, efficiencies, or positive feedback you got.

โžค ๐—ง๐—ฒ๐—ฎ๐—บ ๐—–๐—ผ๐—น๐—น๐—ฎ๐—ฏ๐—ผ๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป:
- Talk about how you collaborated. What was your role in the team? How did you communicate and contribute to the teamโ€™s success?

โžค ๐—Ÿ๐—ฒ๐—ฎ๐—ฟ๐—ป๐—ถ๐—ป๐—ด ๐—ฎ๐—ป๐—ฑ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—บ๐—ฒ๐—ป๐˜:
- Reflect on what you learned from the project. What new skills did you gain, and what would you do differently next time?

โžค ๐—ง๐—ถ๐—ฝ๐˜€ ๐—ณ๐—ผ๐—ฟ ๐—ฌ๐—ผ๐˜‚๐—ฟ ๐—œ๐—ป๐˜๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ฒ๐˜„ ๐—ฃ๐—ฟ๐—ฒ๐—ฝ๐—ฎ๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป:
- Be ready with a 30 second elevator pitch about your projects, and also have a five-minute detailed overview ready.
- If thereโ€™s a pause after you describe the project, donโ€™t hesitate to ask if theyโ€™d like more details or if thereโ€™s a specific part theyโ€™re interested in.

By preparing your project details thoroughly and understanding what the interviewer is looking for, you can talk about your experience in a way that really showcases your skills and increases your chances of getting the job.

Coding Projects: https://whatsapp.com/channel/0029VazkxJ62UPB7OQhBE502
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Complete DSA Roadmap

|-- Basic_Data_Structures
| |-- Arrays
| |-- Strings
| |-- Linked_Lists
| |-- Stacks
| โ””โ”€ Queues
|
|-- Advanced_Data_Structures
| |-- Trees
| | |-- Binary_Trees
| | |-- Binary_Search_Trees
| | |-- AVL_Trees
| | โ””โ”€ B-Trees
| |
| |-- Graphs
| | |-- Graph_Representation
| | | |- Adjacency_Matrix
| | | โ”” Adjacency_List
| | |
| | |-- Depth-First_Search
| | |-- Breadth-First_Search
| | |-- Shortest_Path_Algorithms
| | | |- Dijkstra's_Algorithm
| | | โ”” Bellman-Ford_Algorithm
| | |
| | โ””โ”€ Minimum_Spanning_Tree
| | |- Prim's_Algorithm
| | โ”” Kruskal's_Algorithm
| |
| |-- Heaps
| | |-- Min_Heap
| | |-- Max_Heap
| | โ””โ”€ Heap_Sort
| |
| |-- Hash_Tables
| |-- Disjoint_Set_Union
| |-- Trie
| |-- Segment_Tree
| โ””โ”€ Fenwick_Tree
|
|-- Algorithmic_Paradigms
| |-- Brute_Force
| |-- Divide_and_Conquer
| |-- Greedy_Algorithms
| |-- Dynamic_Programming
| |-- Backtracking
| |-- Sliding_Window_Technique
| |-- Two_Pointer_Technique
| โ””โ”€ Divide_and_Conquer_Optimization
| |-- Merge_Sort_Tree
| โ””โ”€ Persistent_Segment_Tree
|
|-- Searching_Algorithms
| |-- Linear_Search
| |-- Binary_Search
| |-- Depth-First_Search
| โ””โ”€ Breadth-First_Search
|
|-- Sorting_Algorithms
| |-- Bubble_Sort
| |-- Selection_Sort
| |-- Insertion_Sort
| |-- Merge_Sort
| |-- Quick_Sort
| โ””โ”€ Heap_Sort
|
|-- Graph_Algorithms
| |-- Depth-First_Search
| |-- Breadth-First_Search
| |-- Topological_Sort
| |-- Strongly_Connected_Components
| โ””โ”€ Articulation_Points_and_Bridges
|
|-- Dynamic_Programming
| |-- Introduction_to_DP
| |-- Fibonacci_Series_using_DP
| |-- Longest_Common_Subsequence
| |-- Longest_Increasing_Subsequence
| |-- Knapsack_Problem
| |-- Matrix_Chain_Multiplication
| โ””โ”€ Dynamic_Programming_on_Trees
|
|-- Mathematical_and_Bit_Manipulation_Algorithms
| |-- Prime_Numbers_and_Sieve_of_Eratosthenes
| |-- Greatest_Common_Divisor
| |-- Least_Common_Multiple
| |-- Modular_Arithmetic
| โ””โ”€ Bit_Manipulation_Tricks
|
|-- Advanced_Topics
| |-- Trie-based_Algorithms
| | |-- Auto-completion
| | โ””โ”€ Spell_Checker
| |
| |-- Suffix_Trees_and_Arrays
| |-- Computational_Geometry
| |-- Number_Theory
| | |-- Euler's_Totient_Function
| | โ””โ”€ Mobius_Function
| |
| โ””โ”€ String_Algorithms
| |-- KMP_Algorithm
| โ””โ”€ Rabin-Karp_Algorithm
|
|-- OnlinePlatforms
| |-- LeetCode
| |-- HackerRank
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Here are some essential SQL tips for beginners ๐Ÿ‘‡๐Ÿ‘‡

โ—† Primary Key = Unique Key + Not Null constraint
โ—† To perform case insensitive search use UPPER() function ex. UPPER(customer_name) LIKE โ€˜A%Aโ€™
โ—† LIKE operator is for string data type
โ—† COUNT(*), COUNT(1), COUNT(0) all are same
โ—† All aggregate functions ignore the NULL values
โ—† Aggregate functions MIN, MAX, SUM, AVG, COUNT are for int data type whereas STRING_AGG is for string data type
โ—† For row level filtration use WHERE and aggregate level filtration use HAVING
โ—† UNION ALL will include duplicates where as UNION excludes duplicates 
โ—† If the results will not have any duplicates, use UNION ALL instead of UNION
โ—† We have to alias the subquery if we are using the columns in the outer select query
โ—† Subqueries can be used as output with NOT IN condition.
โ—† CTEs look better than subqueries. Performance wise both are same.
โ—† When joining two tables , if one table has only one value then we can use 1=1 as a condition to join the tables. This will be considered as CROSS JOIN.
โ—† Window functions work at ROW level.
โ—† The difference between RANK() and DENSE_RANK() is that RANK() skips the rank if the values are the same.
โ—† EXISTS works on true/false conditions. If the query returns at least one value, the condition is TRUE. All the records corresponding to the conditions are returned.

Like for more ๐Ÿ˜„๐Ÿ˜„
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Top 50 OOPS Interview Preparation Course ๐Ÿ’ปโœ…
โค1๐Ÿ‘1
Here are 20 essential VS Code shortcuts for beginners:

1. Ctrl + P: Open any file quickly ๐Ÿ“‚

2. Ctrl + /: Toggle line comment ๐Ÿ“

3. Alt + Up/Down: Move a line up or down โ†•๏ธ

4. Ctrl + Shift + K: Delete the current line โŒ

5. Ctrl + B: Show/hide the sidebar ๐Ÿ“š

6. Ctrl + Space: Trigger IntelliSense for code suggestions ๐Ÿ’ก

7. Ctrl + Shift + F: Search across files ๐Ÿ”

8. Ctrl + D: Select the next occurrence of the selected text ๐Ÿ“‘

9. Ctrl + Shift + L: Select all occurrences of the current selection ๐Ÿ”—

10. Ctrl + Shift + P: Open the Command Palette ๐Ÿ“œ

11. Ctrl + F2: Rename all occurrences of a variable โœ๏ธ

12. Ctrl + J: Show/hide the integrated terminal ๐Ÿ’ป

13. Ctrl + `: Open a new terminal ๐Ÿ”ง

14. Ctrl + Shift + N: Open a new window ๐Ÿ–ผ๏ธ

15. Ctrl + W: Close the current editor tab ๐Ÿ—‚๏ธ

16. Ctrl + Shift + E: Focus on the file explorer ๐Ÿ—ƒ๏ธ

17. Ctrl + Shift + G: Open the Git view ๐Ÿ”„

18. Ctrl + Shift + M: Open the Problems panel ๐Ÿšจ

19. Alt + Shift + Up/Down: Copy the line up or down ๐Ÿ“‹

20. Ctrl + Alt + Arrow keys: Split the editor window โœ‚๏ธ


Master these and level up your coding speed! ๐Ÿš€
โค4๐Ÿ‘1
9 tips to prepare for coding interviews:

Master DSA fundamentals (arrays, strings, trees, graphs)

Practice daily on LeetCode, Codeforces, or HackerRank

Solve problems under time constraints

Review commonly asked interview patterns

Mock interviews help reduce anxiety

Understand the โ€œwhyโ€ behind each solution

Prepare clean, structured explanations

Brush up on system design and OOP basics

Stay consistent โ€” prep a little every day

Coding Interview Resources:๐Ÿ‘‡ https://whatsapp.com/channel/0029VammZijATRSlLxywEC3X

ENJOY LEARNING ๐Ÿ‘๐Ÿ‘
โค3๐Ÿ‘1
In 1994, people told me programming was for nerds and that I should become a doctor or a lawyer instead.

10 years later, they told me that someone from India would take my job for $5/hour.

Then, no code was going to doom my career.

In 2021, Codex, then Copilot, then ChatGPT, then Devin, then OpenAI o1...

People keep yelling that "Programming is Dead," and yet the demand for good Software Engineers has never been higher.

Stop listening to midwit people. Learn to build good software, and you'll be okay. (Credits: unknown)
๐Ÿ‘8โค2
Best way to prepare for a SQL interviews ๐Ÿ‘‡๐Ÿ‘‡

1. Review Basic Concepts: Ensure you understand fundamental SQL concepts like SELECT statements, JOINs, GROUP BY, and WHERE clauses.

2. Practice SQL Queries: Work on writing and executing SQL queries. Practice retrieving, updating, and deleting data.

3. Understand Database Design: Learn about normalization, indexes, and relationships to comprehend how databases are structured.

4. Know Your Database: If possible, find out which database system the company uses (e.g., MySQL, PostgreSQL, SQL Server) and familiarize yourself with its specific syntax.

5. Data Types and Constraints: Understand various data types and constraints such as PRIMARY KEY, FOREIGN KEY, and UNIQUE constraints.

6. Stored Procedures and Functions: Learn about stored procedures and functions, as interviewers may inquire about these.

7. Data Manipulation Language (DML): Be familiar with INSERT, UPDATE, and DELETE statements.

8. Data Definition Language (DDL): Understand statements like CREATE, ALTER, and DROP for database and table management.

9. Normalization and Optimization: Brush up on database normalization and optimization techniques to demonstrate your understanding of efficient database design.

10. Troubleshooting Skills: Be prepared to troubleshoot queries, identify errors, and optimize poorly performing queries.

11. Scenario-Based Questions: Practice answering scenario-based questions. Understand how to approach problems and design solutions.

12. Latest Trends: Stay updated on the latest trends in database technologies and SQL best practices.

13. Review Resume Projects: If you have projects involving SQL on your resume, be ready to discuss them in detail.

14. Mock Interviews: Conduct mock interviews with a friend or use online platforms to simulate real interview scenarios.

15. Ask Questions: Prepare questions to ask the interviewer about the company's use of databases and SQL.

Best Resources to learn SQL ๐Ÿ‘‡

SQL Topics for Data Analysts

SQL Udacity Course

Download SQL Cheatsheet

SQL Interview Questions

Learn & Practice SQL

Also try to apply what you learn through hands-on projects or challenges.

Please give us credits while sharing: -> https://t.me/free4unow_backup

ENJOY LEARNING ๐Ÿ‘๐Ÿ‘
โค4
The Only roadmap you need to become an ML Engineer ๐Ÿฅณ

Phase 1: Foundations (1-2 Months)
๐Ÿ”น Math & Stats Basics โ€“ Linear Algebra, Probability, Statistics
๐Ÿ”น Python Programming โ€“ NumPy, Pandas, Matplotlib, Scikit-Learn
๐Ÿ”น Data Handling โ€“ Cleaning, Feature Engineering, Exploratory Data Analysis

Phase 2: Core Machine Learning (2-3 Months)
๐Ÿ”น Supervised & Unsupervised Learning โ€“ Regression, Classification, Clustering
๐Ÿ”น Model Evaluation โ€“ Cross-validation, Metrics (Accuracy, Precision, Recall, AUC-ROC)
๐Ÿ”น Hyperparameter Tuning โ€“ Grid Search, Random Search, Bayesian Optimization
๐Ÿ”น Basic ML Projects โ€“ Predict house prices, customer segmentation

Phase 3: Deep Learning & Advanced ML (2-3 Months)
๐Ÿ”น Neural Networks โ€“ TensorFlow & PyTorch Basics
๐Ÿ”น CNNs & Image Processing โ€“ Object Detection, Image Classification
๐Ÿ”น NLP & Transformers โ€“ Sentiment Analysis, BERT, LLMs (GPT, Gemini)
๐Ÿ”น Reinforcement Learning Basics โ€“ Q-learning, Policy Gradient

Phase 4: ML System Design & MLOps (2-3 Months)
๐Ÿ”น ML in Production โ€“ Model Deployment (Flask, FastAPI, Docker)
๐Ÿ”น MLOps โ€“ CI/CD, Model Monitoring, Model Versioning (MLflow, Kubeflow)
๐Ÿ”น Cloud & Big Data โ€“ AWS/GCP/Azure, Spark, Kafka
๐Ÿ”น End-to-End ML Projects โ€“ Fraud detection, Recommendation systems

Phase 5: Specialization & Job Readiness (Ongoing)
๐Ÿ”น Specialize โ€“ Computer Vision, NLP, Generative AI, Edge AI
๐Ÿ”น Interview Prep โ€“ Leetcode for ML, System Design, ML Case Studies
๐Ÿ”น Portfolio Building โ€“ GitHub, Kaggle Competitions, Writing Blogs
๐Ÿ”น Networking โ€“ Contribute to open-source, Attend ML meetups, LinkedIn presence

Follow this advanced roadmap to build a successful career in ML!

The data field is vast, offering endless opportunities so start preparing now.
โค2
Python Interview Questions:

Ready to test your Python skills? Letโ€™s get started! ๐Ÿ’ป


1. How to check if a string is a palindrome?

def is_palindrome(s):
return s == s[::-1]

print(is_palindrome("madam")) # True
print(is_palindrome("hello")) # False

2. How to find the factorial of a number using recursion?

def factorial(n):
if n == 0 or n == 1:
return 1
return n * factorial(n - 1)

print(factorial(5)) # 120

3. How to merge two dictionaries in Python?

dict1 = {'a': 1, 'b': 2}
dict2 = {'c': 3, 'd': 4}

# Method 1 (Python 3.5+)
merged_dict = {**dict1, **dict2}

# Method 2 (Python 3.9+)
merged_dict = dict1 | dict2

print(merged_dict)

4. How to find the intersection of two lists?

list1 = [1, 2, 3, 4]
list2 = [3, 4, 5, 6]

intersection = list(set(list1) & set(list2))
print(intersection) # [3, 4]

5. How to generate a list of even numbers from 1 to 100?

even_numbers = [i for i in range(1, 101) if i % 2 == 0]
print(even_numbers)

6. How to find the longest word in a sentence?

def longest_word(sentence):
words = sentence.split()
return max(words, key=len)

print(longest_word("Python is a powerful language")) # "powerful"

7. How to count the frequency of elements in a list?

from collections import Counter

my_list = [1, 2, 2, 3, 3, 3, 4]
frequency = Counter(my_list)
print(frequency) # Counter({3: 3, 2: 2, 1: 1, 4: 1})

8. How to remove duplicates from a list while maintaining the order?

def remove_duplicates(lst):
return list(dict.fromkeys(lst))

my_list = [1, 2, 2, 3, 4, 4, 5]
print(remove_duplicates(my_list)) # [1, 2, 3, 4, 5]

9. How to reverse a linked list in Python?

class Node:
def __init__(self, data):
self.data = data
self.next = None

def reverse_linked_list(head):
prev = None
current = head
while current:
next_node = current.next
current.next = prev
prev = current
current = next_node
return prev

# Create linked list: 1 -> 2 -> 3
head = Node(1)
head.next = Node(2)
head.next.next = Node(3)

# Reverse and print the list
reversed_head = reverse_linked_list(head)
while reversed_head:
print(reversed_head.data, end=" -> ")
reversed_head = reversed_head.next

10. How to implement a simple binary search algorithm?

def binary_search(arr, target):
low, high = 0, len(arr) - 1
while low <= high:
mid = (low + high) // 2
if arr[mid] == target:
return mid
elif arr[mid] < target:
low = mid + 1
else:
high = mid - 1
return -1

print(binary_search([1, 2, 3, 4, 5, 6, 7], 4)) # 3


Here you can find essential Python Interview Resources๐Ÿ‘‡
https://t.me/DataSimplifier

Like for more resources like this ๐Ÿ‘ โ™ฅ๏ธ

Share with credits: https://t.me/sqlspecialist

Hope it helps :)
โค6
Java coding interview questions

1. Reverse a String:
Write a Java program to reverse a given string.
2. Find the Largest Element in an Array:
Find and print the largest element in an array.
3. Check for Palindrome:
Determine if a given string is a palindrome (reads the same backward as forward).
4. Factorial Calculation:
Write a function to calculate the factorial of a number.
5. Fibonacci Series:
Generate the first n numbers in the Fibonacci sequence.
6. Check for Prime Number:
Write a program to check if a given number is prime.
7. String Anagrams:
Determine if two strings are anagrams of each other.

8. Array Sorting:
Implement sorting algorithms like bubble sort, merge sort, or quicksort.

9. Binary Search:
Implement a binary search algorithm to find an element in a sorted array.

10. Duplicate Elements in an Array:
Find and print duplicate elements in an array.

11. Linked List Reversal:
Reverse a singly-linked list.

12. Matrix Operations:
Perform matrix operations like addition, multiplication, or transpose.

13. Implement a Stack:
Create a stack data structure and implement basic operations (push, pop).

14. Implement a Queue:
Create a queue data structure and implement basic operations (enqueue, dequeue).

15. Inheritance and Polymorphism:
Implement a class hierarchy with inheritance and demonstrate polymorphism.

16. Exception Handling:
Write code that demonstrates the use of try-catch blocks to handle exceptions.
17. File I/O:
Read from and write to a file using Java's file I/O capabilities.
18. Multithreading:
Create a simple multithreaded program and demonstrate thread synchronization.
19. Lambda Expressions:
Use lambda expressions to implement functional interfaces.
20. Recursive Algorithms:
Solve a problem using recursion, such as computing the factorial or Fibonacci sequence.

Best Java Resources: https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s

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