Daily Coding Challenges & Projects

Frontend Mini Project Challenge

JavaScript Puzzle

Project :

Write a function that checks whether a given number is a palindrome without converting it to a string.

Hint : Use arithmetic (modulus, division) to reverse the number.

JavaScript Debugging

let result = 0;
for (var i = 0; i < 5; i++) {
  setTimeout(() => {
    console.log(i); // What's the issue?
  }, 1000);
}

Fix : Use let, IIFE, or closures to preserve loop state.

Try It Online :

CodePen

JSFiddle

Backend Challenge

Language Focus : C, C++, C#

C Challenge :

Write a C program to reverse a singly linked list

C++ Challenge :

Implement a simple file logger class that appends timestamped logs to a file.

C# Challenge :

Create a Web API using ASP.NET Core that returns a list of users in JSON format.

Database Query Challenge

Problems on SQL - HR Database :

1. List employees who joined in the last 90 days.
2. Find departments where average salary is below 50,000.

Data Structures & Algorithms Challenge

• Easy:
• Problem :Find the second largest number in an array
• Hint :Track top two elements in one pass.
• Medium:
• Problem : Implement a queue using two stacks
• Hint :Use two stacks to simulate enqueue/dequeue.
• Hard:
• Problem :Longest substring without repeating characters
• Hint :Sliding window + hash set.

Bug of the Day

Language : C

C Bug

Buggy Code:

#include 
int main() {
    char *str = "Hello";
    str[0] = 'h';
    printf("%s", str);
    return 0;
}

Bug :You're modifying a string literal.

Fix :Use char str[] = "Hello";

📋 Daily Micro-Project

Frontend :

Task :

Build a tooltip component using only HTML/CSS.

Bonus : Position it top/bottom using CSS variables.

Trivia: 5 Fun Facts

1. JavaScript was created in 10 days by Brendan Eich.
2. C++ was originally called C with Classes.
3. C# was developed by Microsoft as part of the .NET initiative.
4. The first web browser was called WorldWideWeb.
5. The <canvas> element was introduced in HTML5.

Tool & Resource of the Day

Tool : CodeSandbox

CodeSandbox

A powerful online editor for React, Vue, Angular projects.

Resource Roundup :

• Frontend Mentor – Real-world frontend projects
• CSS Tricks – Expert tips on all things CSS

Interview Question of the Day

Daily Interview Questions

Frontend ( JS-Focused ) :
1. What is the difference between == and ===?
2. How does hoisting work in JavaScript?
3. Explain the event loop and call stack.
4. What are closures and how are they used?

Backend ( C, C++, C# ) :
1. What is a memory leak in C/C++?
2. How does garbage collection work in C#?
3. What is a segmentation fault?
4. What are value types vs reference types in C#?

Database :
1. What is a foreign key?
2. How do indexes work in databases?
3. Difference between WHERE and HAVING.

Others :
1. What is a system call?
2. How is multithreading different from multiprocessing?

Daily Quiz Challenge

Frontend ( JS ) :

1. What is the output of typeof NaN?
2. Can you reassign const objects?
3. What does [].push(1, 2).pop() return?

Backend ( C, C++, C# ) :

1. Which keyword is used in C# to define an interface?
2. What is malloc used for in C?
3. C++ STL: What does a set do?

Others :

• DB: What does GROUP BY do?
• System: What does the fork() system call return?

Weekly Cross-Domain Activities ( July 18 to July 24, 2025 )

API of the Day:

JokeAPI : Build a random joke app with categories and flags (NSFW filter).

Linux/DevOps Tip :

Use htop, iotop, and iftop to monitor CPU, disk, and network usage on Linux servers.

Real-World Project of the Week ( July 18 to July 24, 2025 )

Project of the Week:

Build a Task Manager App

• Use React + Express + MongoDB
• Support CRUD: Tasks with due dates, priority, and status
• Implement filters (Today, Completed, Priority)

Collaborative Project:

Start a GitHub repo for this task manager and invite others to contribute (issues, PRs, README).

Case Study:

Analyze the GitHub UI/UX — Can you recreate the repository page using frontend tools?