How to Print Butterfly Star Pattern in PHP – Step-by-Step Tutorial

For n = 5, the pattern looks like:

This has two parts:

1. Upper Half – Rows from 1 to n
2. Lower Half – Rows from n to 1

🧠 Logic Behind It

For any row i:

• Print i stars
• Print 2 * (n - i) spaces
• Print i stars again

📝 Full PHP Code with Comments

<?php
$n = 5; // You can change this number for larger pattern

// Upper half of the butterfly
for ($i = 1; $i <= $n; $i++) {
    // Left stars
    for ($j = 1; $j <= $i; $j++) {
        echo "*";
    }

    // Spaces
    for ($j = 1; $j <= 2 * ($n - $i); $j++) {
        echo " ";
    }

    // Right stars
    for ($j = 1; $j <= $i; $j++) {
        echo "*";
    }

    // New line
    echo "\n";
}

// Lower half of the butterfly
for ($i = $n; $i >= 1; $i--) {
    // Left stars
    for ($j = 1; $j <= $i; $j++) {
        echo "*";
    }

    // Spaces
    for ($j = 1; $j <= 2 * ($n - $i); $j++) {
        echo " ";
    }

    // Right stars
    for ($j = 1; $j <= $i; $j++) {
        echo "*";
    }

    // New line
    echo "\n";
}
?>

▶️ How It Works

Hey guys! 👋 Today, we’re building a butterfly star pattern in PHP 🦋

👉 Step 1: We decide how many rows we want. Let’s say $n = 5.

👉 Step 2: For the upper half, we loop from 1 to n. Each row:

• Adds stars on the left ($i times)
• Then spaces in the middle (2 * (n - i) times)
• Then again stars on the right ($i times)

👉 Step 3: For the lower half, we just reverse it – loop from $n down to 1.

And voilà! You get this beautiful symmetrical butterfly.

Would you like the HTML version too for browser output? Or maybe a video script for a full YouTube-style tutorial? 😄