DEsaulenko/hw18. Практикум решения алгоритмических задач 2

.gitignore

@@ -14,3 +14,4 @@
 # Другие файлы
 .idea/
 .DS_Store
+vendor/

README.md

@@ -1,3 +1,9 @@
 # PHP_2023
 
-https://otus.ru/lessons/razrabotchik-php/?utm_source=github&utm_medium=free&utm_campaign=otus
+### HW18
+
+#### https://leetcode.com/problems/intersection-of-two-linked-lists/
+Сложность 0(n+m)
+
+#### https://leetcode.com/problems/fraction-to-recurring-decimal/
+Сложность 0(n)

app/composer.json

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+{
+    "name": "desaulenko/hw18",
+    "type": "library",
+    "autoload": {
+        "psr-4": {
+            "DEsaulenko\\Hw18\\": "src/"
+        }
+    },
+    "require": {
+        "symfony/var-dumper": "^6.3"
+    }
+}

app/fraction-to-recurring-decimal.php

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+<?php
+
+declare(strict_types=1);
+
+namespace DEsaulenko\Hw18\Fraction;
+
+require_once 'vendor/autoload.php';
+
+/**
+ * Definition for a singly-linked list.
+ * class ListNode {
+ *     public $val = 0;
+ *     public $next = null;
+ *     function __construct($val) { $this->val = $val; }
+ * }
+ */
+class Solution
+{
+    /**
+     * @param Integer $numerator
+     * @param Integer $denominator
+     * @return String
+     */
+    public function fractionToDecimal($numerator, $denominator)
+    {
+        if ($denominator === 0) {
+            return '';
+        }
+
+        $negative = ($numerator * $denominator) < 0 ? '-' : '';
+
+        $numerator = abs($numerator);
+        $denominator = abs($denominator);
+
+        $left = floor($numerator / $denominator);
+        $right = $this->prepareRight($numerator, $denominator);
+
+        return $negative . $left . $right;
+    }
+
+    protected function prepareRight($numerator, $denominator)
+    {
+        $result = '.';
+
+        $store = [];
+        $tmp = $numerator % $denominator;
+        while ($tmp !== 0) {
+            $store[$tmp] = strlen($result);
+            $tmp *= 10;
+            $cur = floor($tmp / $denominator);
+            $tmp %= $denominator;
+            if (isset($store[$tmp])) {
+                return substr($result, 0, $store[$tmp]) . "(" . substr($result, $store[$tmp]) . $cur . ")";
+            }
+            $result .= $cur;
+        }
+
+        return $result === '.' ? '' : $result;
+    }
+}
+
+$numerators = [1, 2, 4, 1, 4, 6, 4, 1, -50, 1];
+$denumerators = [2, 1, 333, 3, 3, 73, 11, 6, 8, 214748364];
+$solution = new Solution();
+foreach ($numerators as $i => $val) {
+    dump([
+        $val / $denumerators[$i],
+        $solution->fractionToDecimal($val, $denumerators[$i])
+    ]);
+}