Question

I have an array that already contains all it’s values in alphabetical order:

Alligator
Alpha
Bear
Bees
Banana
Cat
Cougar

Now I just want to list the first letter each starts with above it like so:

A
---

Alligator
Alpha

B
---

Bear
Bees
Banana

C
---

Cat
Cougar

etc...

How can this be done?

Answer 1

The solution is to keep in a variable the first letter of the previously printed word, like:

$previous = null;
foreach($array as $value) {
    $firstLetter = substr($value, 0, 1);
    if($previous !== $firstLetter) echo "\n".$firstLetter."\n---\n\n";
    $previous = $firstLetter;

    echo $value."\n";
}

NB: if some entries start with a lower-case letter and others with upper-case letters, use the strcasecmp function in the test instead of !==.