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Yashwanth Reddy Boreddy
Yashwanth Reddy Boreddy

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When Patterns Stop Being About Patterns: My Battle With the Spiral (Snail) Matrix

This is my breakthrough journey, how I finally cracked one of the most head breaking pattern problems I’ve ever faced.

1 2 3
8 9 4
7 6 5
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This thing looks innocent.
It is not.

I struggled with this for more than a day. Literally stuck.
Out of an assignment of 85 pattern questions, this was the last one, it felt intentionally designed to break us so we couldn’t complete the set.

Where My Brain Got Stuck

After solving 80+ pattern problems using loops in JavaScript, my brain had been trained (or ruined) to see everything as:

  • math based
  • loop based
  • i and j manipulation
  • stars, numbers, symmetry

Triangles.
Inverted triangles.
Pyramids.
Hourglasses.
Butterflies.
Hollow patterns.
If it had a name, I probably printed it.

So when this came up, my brain automatically tried to force a mathematical formula out of it.

I kept asking questions like:

  • How do I manipulate i and j?
  • Can I tweak loop conditions?
  • Is there some magic equation behind this?

And that was the mistake.

I wasn’t looking at it as rows and columns.
I wasn’t seeing it as a matrix.
I was trying to treat it like a normal pattern problem and it just refused to cooperate.

The Mental Shift That Changed Everything

The breakthrough didn’t come from more loops.
It came from changing how I looked at the problem.

This was not a pattern problem.
This was a matrix traversal problem disguised as a pattern.

Once I started treating the output as a 2D grid, things slowly started making sense.

Even then, I won’t lie... the brainstorming continued.
I still couldn’t see the full solution immediately.
But at least now, I had a direction.

And that was something I didn’t even have before.

Thinking in Boundaries, Not Formulas

Instead of trying to calculate positions, the idea was simple:

Fill the matrix layer by layer

Move in four directions

  1. left → right
  2. top → bottom
  3. right → left
  4. bottom → top

Shrink the boundaries after each pass

This is where top, bottom, left, and right come in.

The Code That Finally Worked

let n = 3;

let matrix = Array.from({ length: n }, () => Array(n).fill(0));

//let matrix = [
//    [1, 2, 3],
//    [4, 5, 6],
//    [7, 8, 9]
//];

let num = 1;

// Boundaries
let top = 0, bottom = n - 1;
let left = 0, right = n - 1;

while (num <= n * n) {

    // left → right
    for (let i = left; i <= right; i++) {
        matrix[top][i] = num++;
    }
    top++;

    // top → bottom
    for (let i = top; i <= bottom; i++) {
        matrix[i][right] = num++;
    }
    right--;

    // right → left
    for (let i = right; i >= left; i--) {
        matrix[bottom][i] = num++;
    }
    bottom--;

    // bottom → top
    for (let i = bottom; i >= top; i--) {
        matrix[i][left] = num++;
    }
    left++;
}

// Print result
for (let row of matrix) {
    console.log(row.join(' '));
}
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What’s Actually Happening Here (Plain English)

num keeps increasing from 1 to n * n

top, bottom, left, right define the current layer

Each loop fills one side of the spiral

After finishing a side, we move the boundary inward

The while loop ensures we stop exactly when the matrix is full

No formulas.
No pattern tricks.
Just controlled movement.

About That Array.from() Thing

At first, I directly wrote the matrix values manually.

Later, I switched to something like this:

let matrix = Array.from({ length: n }, () => Array(n).fill(0));

No BS,
I was using it without fully understanding it at first and I still don't.

But here’s what it does:

Creates an array with n rows

Each row is a new array of size n

Fills everything with 0

Prevents reference issues (which is important)

This allows the same logic to work for any size, not just 3 × 3.

The Real Lesson (Not the Code)

This problem taught me something bigger than spiral matrices:

Sometimes the problem isn’t hard
your mental model is wrong.

I wasn’t failing because I didn’t know loops.
I was failing because I was trying to force the problem into a shape it wasn’t.

Once I stopped treating it as a pattern and started treating it as a matrix traversal, everything clicked.

And yeah I needed guidance.
But more importantly, I needed a shift in perspective.

That’s the shell I finally cracked

Ending this before I over explain
I’m still new to this.

This question didn’t make me feel smart it made me feel stuck, then relieved.

If you’re struggling with this pattern, you’re not alone. It’s confusing until it isn’t.

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