Count the number of times you can make a given word from the letters of a larger text

Question

I wanted to make a function which you can see how many times you can make a given word from a text.

For example:

The text is: Ham followed now ecstatic use speaking exercise may repeated. Himself he evident oh greatly my on inhabit general concern. It allowance prevailed enjoyment in it. Calling observe for who pressed raising his. Can connection instrument astonished unaffected his motionless preference. Announcing say boy precaution unaffected difficulty alteration him.

$text = "Ham followed now ecstatic use speaking exercise may repeated.
Himself he evident oh greatly my on inhabit general concern. It allowance 
prevailed enjoyment in it. Calling observe for who pressed raising his. Can 
connection instrument astonished unaffected his motionless preference. 
Announcing say boy precaution unaffected difficulty alteration him.";

$word = "Potato";

I want to know how many times you can write the word "potato". The expected count is 6 times.

I started with something like this:

function count($text) {
    for ($i = 0; $i <= strlen($text); $i++) {
        if ($text[$i] == "p") {
            $p = 0;
            $p++;
            echo $p;
        }
    }
}

Answer 1

Firstly, you cannot redeclare a count() function -- it is already declared as a native function in PHP.

Try this recursive function which contains nested loops:

function countt($text, $word, $count = 0) {
    $found = '';
    for ($i = 0; $i < strlen($word); $i++) {
        for ($j = 0; $j < strlen($text); $j++) {
            if ($word[$i] === $text[$j]) {
                $text = substr($text, 0, $j) . substr($text, $j + 1);
                $found .= $word[$i];
                if ($found === $word) {
                    $count++;
                    return countt($text, $word, $count);
                }
                break;
            }
        }
    }
    return $count;
}

echo countt($text, 'potato');//6

Explanation: This recursive function finds occurrences of each letter of a word in text and removes it from the text. Once it completes the new word that is identical to the searched one, it calls this function again with new text, that misses those used letters, until there is no more letters left that could complete another word.

You can play with it here: https://3v4l.org/h43rq

Answer 2

this function help you to get how many times paroto has used in that string

echo substr_count($text, $word);

Answer 3

My approach would be to go through the text storing each character in a dictionary where the key is the letter and the value is the number of occurrences in the text. Once you finish processing the text you can calculate how many times you can spell potato

Answer 4

After converting both input strings (assumed to only contain single byte characters) to lowercase, call count_chars() on both strings to populate maps of characters and their number of occurrences.

Then loop over the needle's letters and calculate how many times the letter is found and how many times it is used per whole input "word".

Maintain the lowest calculated value as your iterate and break the loop as soon as the value becomes zero.

Code: (Demo)

$needleCharCounts = count_chars(strtolower($word), 1);
$haystackCharCounts = count_chars(strtolower($text), 1);

$result = null;
foreach ($needleCharCounts as $letter => $count) {
    $result = min($result ?? PHP_INT_MAX, intdiv($haystackCharCounts[$letter] ?? 0, $count));
    if ($result === 0) {
        break;
    }
}
echo $result ?? 0;
// 6