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Daily Coding Challenges & Projects


Monday


Frontend Mini Project Challenge

Theme : JavaScript Logical Puzzle & Debugging

Challenge :

Write a function to deeply clone a nested object without using JSON.stringify.

Requirements :

  • Handle arrays, objects, and nested structures.
  • Preserve data types like Date or RegExp.

Bonus : Support circular references detection.

Backend Challenge

Language Focus : C, C++, C#

C# Task :

Create a program to reverse a singly linked list.

Bonus : Make the function generic to handle any data type.

Database Query Challenge

Problems on SQL - HR Database :

  1. Write a query to find employees who joined in the last 6 months and work in the 'Sales' department.
  2. Write a query to list managers who supervise more than 3 employees.

HR database



Data Structures & Algorithms Challenge

  • Easy:
    • Problem : Find the maximum element in an array.
    • Hint : Iterate through array and track max.
  • Medium:
    • Problem : Implement a stack using two queues.
    • Hint : One queue holds data, other assists with operations.
  • Hard:
    • Problem :Detect a cycle in a directed graph.
    • Hint : Use DFS with recursion stack tracking.

Bug of the Day

Language : C

C Bug

    Buggy Code:

    
    #include 
    
    int main() {
        int x = 5;
        if (x = 10) {
            printf("X is ten\n");
        }
        return 0;
    }
    

Challenge :

Find and fix the bug.

Hint : Assignment or comparison?

📋 Daily Micro-Project

Frontend Focus :

Task :

    Build a CSS-only animated loading spinner with dots or bars.

Bonus: Add accessibility features (ARIA labels).

Trivia: 5 Fun Facts

  1. C was developed in 1972 by Dennis Ritchie.
  2. C++ adds object-oriented features to C.
  3. C# is primarily used for .NET applications.
  4. JavaScript was created in just 10 days.
  5. Debugging term originates from removing actual bugs from hardware.

Tool & Resource of the Day

Tool : JSFiddle

Online playground to test JavaScript, CSS, and HTML.

https://jsfiddle.net/

Resource Roundup : JavaScript Debugging

  • Debugging JavaScript Crash Course (YouTube)
  • Chrome DevTools Guide
  • Breakpoints & Watchers in VSCode (Blog)

Interview Question of the Day

Daily Interview Questions

    Frontend :
    1. What are closures in JavaScript?
    2. Difference between == and ===?
    3. What is event bubbling?
    4. How does hoisting work?
    Backend :
    1. What is a pointer in C?
    2. Differences between malloc and calloc?
    3. What is encapsulation in C++?
    4. Explain garbage collection in C#.
    Database ( SQL ) :
    1. What is normalization?
    2. Purpose of foreign keys?
    3. Difference between DELETE and TRUNCATE?
    Others :
    1. What is a compiler?
    2. Explain CI/CD.

Daily Quiz Challenge

    Frontend Quiz :

    1. What does === operator check?
      • Value only
      • Type only
      • Value & Type
      • Converts to string
    2. In JavaScript, typeof null returns:
      • "null"
      • "undefined"
      • "object"
      • "boolean"
    3. let vs var - main difference?
      • Scope
      • Speed
      • Compatibility
      • Output format

    Backend Quiz :

    1. What is a struct in C?
      • Function
      • Data container
      • Loop type
      • Memory block
    2. C++ new operator does:
      • Calls a function
      • Allocates memory
      • Deletes memory
      • Prints text
    3. C# interface keyword defines:
      • Inheritance chain
      • Method contract
      • Memory address
      • Static variable

    Database :

    1. What ensures uniqueness in a column?
      • Foreign Key
      • Unique Constraint
      • Primary Key
      • Index

    General :

    1. Which tool compiles code?
      • Browser
      • Compiler
      • Interpreter
      • Linter

Weekly Cross-Domain Activities ( July 04 to July 10, 2025 )

API of the Day:

Task : Build a currency converter using the ExchangeRate-API.

Details :

  • Fetch real-time currency conversion rates using https://www.exchangerate-api.com/.
  • Allow users to select base and target currencies.
  • Display the converted amount dynamically.

Bonus :

  • Add error handling for invalid inputs.
  • Style it with CSS for a clean look.

Linux/DevOps Tip :

5 commands to monitor system performance:

  • top, htop, free -m, df -h, uptime

Real-World Project of the Week ( July 04 to July 10, 2025 )

Project of the Week:

Build a responsive personal portfolio using HTML, CSS, JavaScript, and optionally React.

Collaborative Project:

Contribute to a GitHub open-source project — Suggest projects like https://github.com/firstcontributions/first-contributions

Case Study:

Explore how Netflix uses microservices and scalable cloud infrastructure.


Previous Daily Coding Challenges & Projects : 04-04-2025   07-04-2025  08-04-2025  09-04-2025  10-04-2025  11-04-2025  14-04-2025  15-04-2025  16-04-2025  17-04-2025  18-04-2025  21-04-2025  22-04-2025  23-04-2025  24-04-2025  25-04-2025  28-04-2025  29-04-2025  30-04-2025  01-05-2025  02-05-2025  05-05-2025  06-05-2025  07-05-2025  08-05-2025  09-05-2025  12-05-2025  13-05-2025  14-05-2025  15-05-2025  16-05-2025  19-05-2025  20-05-2025  21-05-2025  22-05-2025  23-05-2025  26-05-2025  27-05-2025  29-05-2025  30-05-2025  02-06-2025  03-06-2025  04-06-2025  05-06-2025  06-06-2025  09-06-2025  10-06-2025  11-06-2025  12-06-2025  13-06-2025  16-06-2025  17-06-2025  18-06-2025  19-06-2025  20-06-2025  23-06-2025  24-06-2025  25-06-2025  26-06-2025  27-06-2025  30-06-2025  01-07-2025  02-07-2025  03-07-2025  04-07-2025



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