Check which of the roman numbers are valid Polish words

polish_numbers_within_roman_numbers.php

<?php

// https://sjp.pl/slownik/growy/

// Firstly, put into separate file only those words that contain only letters making up roman numbers

$handle = fopen("slowa.txt", "r");
$handle_write = fopen("jakby_rzymskie.txt", "w");
if ($handle) {
    while (($line = fgets($handle)) !== false) {
        // process the line read.
		// ['M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I']
		if (trim(str_replace(['m', 'cm', 'd', 'cd', 'c', 'xc', 'l', 'xl', 'x', 'ix', 'v', 'iv', 'i'], '', $line)) == '') {
            fputs($handle_write, $line);
			echo $line;
        }
    }

    fclose($handle);
} else {
    // error opening the file.
}

fclose($handle_write);

/////////////////////////////////////////////////////////////////////

function numberToRomanRepresentation($number) {
    $map = array('M' => 1000, 'CM' => 900, 'D' => 500, 'CD' => 400, 'C' => 100, 'XC' => 90, 'L' => 50, 'XL' => 40, 'X' => 10, 'IX' => 9, 'V' => 5, 'IV' => 4, 'I' => 1);
    $returnValue = '';
    while ($number > 0) {
        foreach ($map as $roman => $int) {
            if($number >= $int) {
                $number -= $int;
                $returnValue .= $roman;
                break;
            }
        }
    }
    return $returnValue;
}

$rzymskie = [];

foreach (range(1, 200000) as $liczba) {
    $rzymskie[$liczba] = strtolower(numberToRomanRepresentation($liczba));
}

$handle = fopen("jakby_rzymskie.txt", "r");
if ($handle) {
    while (($line = fgets($handle)) !== false) {
        // process the line read.
		// ['M', 'CM', 'D', 'CD', 'C', 'XC', 'L', 'XL', 'X', 'IX', 'V', 'IV', 'I']
		foreach ($rzymskie as $liczba => $rzym) {
			if ($rzym == trim($line)) {
				echo $liczba . ' ' . $rzym . PHP_EOL;
			}
		}
    }

    fclose($handle);
} else {
    // error opening the file.
}