tz.php

<?php

//
//1. Write an application which calculates the least amount of Euro-Coins needed for any input amount
//7,21 Euro = 6 Coins (2€+2€+2€+1€+0,2€+0,01€)
//3,72 Euro = 6 Münzen (2€+1€+0,5€+0,2€+0,02€) - >>>> it looks like mistake. Right answer should be 5 coins
class App {

    /**
     * Different coins nominals
     * @var array
     */
    const EURO_COINS = [
        0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 2
    ];

    /**
     * Calculate min amount of coins
     * @param float $amount
     * @return array
     */
    public function calculate($amount)
    {
        if (in_array($amount, self::EURO_COINS)) {
           return [
                'coins' => [$amount],
                'amount' => 1,
            ];
        } else {
            $coins = self::EURO_COINS;
            arsort($coins);

            $result = $this->getCoinsCount($coins, $amount, [
                'coins' => [],
                'amount' => 0,
            ]);

            return $result;
        }
    }

    /**
     * @param array $coins
     * @param integer $amount
     * @param array $result
     * @return array
     */
    private function getCoinsCount($coins, $amount, $result = [])
    {
        foreach ($coins as $coin) {
            if (round($amount, 2) >= round($coin, 2)) {
                $current = (int)($amount / $coin);

                if ($current > 1) {
                    for ( $i = 0; $i < $current; $i++) {
                        $result['coins'][] = $coin;
                        $result['amount'] += 1;
                    }
                } else {
                    $result['coins'][] = $coin;
                    $result['amount'] += 1;
                }
                $amount -= ($current * $coin);
            }
        }

        return $result;
    }

}

//2. Write a function that accepts two parameters, a parent and a child string. Determine how
//many times the child string - or an anagram of the child string - appears in the parent string.
//f('AdnBndAndBdaBn', 'dAn') // 4 ("Adn", "ndA", "dAn", "And")
//f('AbrAcadAbRa', 'cAda') // 2
class Counter {
    /**
     * Count amount of substring (and substring's anagrams)
     * @param string $mainString
     * @param string $substring
     * @return integer
     */
    public function countSubstring($mainString, $substring)
    {
        $amount = 0;
        $anagrams = $this->getAnagrams($substring);

        if (!empty($anagrams)) {
            foreach ($anagrams as $anagram) {
                $amount += substr_count($mainString, $anagram);
            }
        }

        return $amount;
    }

    /**
     * @param string $substring
     * @return array
     */
    private function getAnagrams($substring)
    {
        if (strlen($substring) < 2) {
            return [$substring];
        }

        $combination = substr($substring, 1);
        $result = [];

        foreach ($this->getAnagrams($combination) as $letter) {
            $length = strlen($letter);
            for ($i = 0; $i <= $length; $i++) {
                $result[] = substr($letter, 0, $i) . $substring[0] . substr($letter, $i);
            }
        }

        return array_unique($result);
    }
}

$app = new App();
$answer1 = $app->calculate(7.21);
$answer2 = $app->calculate(3.72);
$answer3 = $app->calculate(2);

echo "<pre>";
print_r($answer1);
echo "<pre>";

echo "<pre>";
print_r($answer2);
echo "<pre>";

echo "<pre>";
print_r($answer3);
echo "<pre>";


$counter = new Counter();
$answer4 = $counter->countSubstring('AdnBndAndBdaBn', 'dAn');
$answer5 = $counter->countSubstring('AbrAcadAbRa', 'cAda');


echo "<pre>";
print_r($answer4);
echo "<pre>";

echo "<pre>";
print_r($answer5);
echo "<pre>";