Building My First C++ Grade Manager: Solving Real Student Problems 📊

Julian — Thu, 23 Jul 2026 03:42:02 +0000

Hey everyone! 👋

As a computer science student, I'm always looking for ways to apply what I learn in class to real-world problems. I firmly believe that building tools you actually need is the best way to learn.

Today, I want to share a fun milestone in my journey as a developer: I just finished my Student Grade Manager project in C++! 🚀

The Problem 🤔

Let's be honest, whether you are in university or school, keeping track of your grades and calculating that final average can be unnecessarily stressful. You are constantly crunching numbers to see what score you need on the final exam to pass the semester.

Instead of relying on random spreadsheets, I decided to code my own solution.

How It Works 💻

The project is a basic but robust grade manager built entirely in C++. It allows a user to input their subjects, track their grades, and automatically calculate their overall average.

It was a great exercise in structuring logic, handling user inputs, and managing data directly from the console.

float calcularPromedioPonderado(const vector<Materia>& materias){
    float promedio = 0;
    int creditosTotal = 0;
    if(materias.size() == 0){
        return 0.0;
    }
    for(const Materia& m : materias){
        promedio += m.nota * m.creditos;
        creditosTotal += m.creditos;
    }
    if(creditosTotal == 0){
        return 0;
    }
    return promedio / creditosTotal;
}

What's Next? 🌐

Now that the core logic is solid in C++, I'm already diving into my next challenge: bringing this tool to the browser! I'm currently working on a fully dynamic web application version using HTML, CSS, and JavaScript. The goal is to build an interactive subject table where students can add their grades on the fly and see their averages update in real-time.

Check it out! 👀

You can check out the source code for the C++ version on my GitHub repository here: 👉 github.com/SRSURY/student-grade-manager-cpp

If you are also learning to code, don't just follow tutorials—build tools for yourself! It changes everything.

Have you ever built a project to solve a personal problem? Let me know in the comments! 👇

Follow my journey as I build in public!

#100DaysOfCode #CodeNewbie #CPP

How a Single Letter Ruined My 2D Array Code for 20 Minutes 😅

Julian — Fri, 03 Jul 2026 05:21:52 +0000

Hey everyone! 👋

Today, while working on my journey as a computer science student, I was tackling a 2D Arrays challenge in JavaScript. Everything seemed perfect. The logic made sense, the loops looked solid... but the code just wouldn't work.

I spent about 20 minutes staring at the screen, running mental tests, and questioning my programming skills.

Can you spot the error in this snippet?

for(let j = 0; j < matrix.length ; j++){
    let value = matrix[j][0];
    for(let k = 0; k < matrix[j].lenght; k++){
        // Logic here
    }
}

Yeah... it was the 't' at the end of matrix[j].lenght. I wrote lenght instead of length.

The JavaScript Trap 🪤

The worst part about this specific typo in JavaScript is that the console won't throw an explicit error. JS just looks at matrix[j].lenght, says "Well, that property doesn't exist, so it's undefined", and moves on.

Since k < undefined evaluates to false, the inner loop never executed, leaving me completely stuck.

My Lesson of the Day 💡

I felt a bit silly when I finally noticed that tiny mistake, but it reminded me of two valuable lessons:

Always check the typos first before assuming your entire logic is broken.
Use linters or spell checkers! (Time to install one in my editor ASAP).

If you are also learning to code, don't feel bad when these things happen. It's a classic rite of passage for every developer!

Have you ever lost hours of work because of a single misplaced letter? Let me know in the comments! 👇

Follow my journey as I build in public! 🚀

DEV Community: Julian