DSA Pattern: A Clean Way to Parse Words from a String

🚀 A Clean Pattern for Word-by-Word String Parsing in PHP

Recently, while solving problems like:

• ✅ Counting segments in a sentence
• ✅ Reversing words
• ✅ Manual string tokenization

I discovered a powerful template for breaking down a string into individual words without using built-in functions like explode() or str_word_count().

Here's the simplified version of the logic:

$sentence = [];
$word = '';

for ($i = 0; $i < strlen($s); $i++) {
    if ($s[$i] !== ' ') {
        // Keep building the word until space is found
        $word .= $s[$i];
    } else {
        // Space hit = word finished, push it to array
       if( $word != '' ){
          $sentence[] = $word;
          $word = ''; // Reset word builder
        }
    }
}

// After loop ends, push the last word (if any)
if ($word !== '') {
    $sentence[] = $word;
}

🧠 What’s happening here?

1. We're looping through each character.
2. If the character is not a space → it's part of a word → build it.
3. If the character is a space → we finished building one word → store it → reset.
4. At the end of the loop, if a word is still in progress, we save it.

💥 Why is this helpful?

• Works even when multiple spaces are between words (after using preg_replace('/\s+/', ' ', $s) to normalize).
• Doesn't rely on external functions, gives you full control.
• Can be adapted to parse custom delimiters or handle punctuation-sensitive input.

✨ Bonus Insight:

The final word in a string is not followed by a space — so it never hits the “else” block. That’s why the if ($word !== '') after the loop is crucial. Without it, your last word would be lost!

📌 Template takeaway:
If you're building tools that deal with sentence parsing, custom formatting, or you're preparing for string-related DSA problems, this small but powerful pattern will keep showing up!

Let me know what you think, or how you'd adapt this for other tasks!