E spiktarenko/hw18

hw18/fraction.php

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+<?php
+// Сложность O(n)
+class Solution {
+
+    /**
+     * @param Integer $numerator
+     * @param Integer $denominator
+     * @return String
+     */
+    function fractionToDecimal($numerator, $denominator) {
+        $number = $numerator/$denominator;
+        $str = "".$number;
+        $dec = explode ('.', $str);
+        $str_dec = $dec[1];
+
+        if ($str_dec==""){
+            return $str;
+        }
+
+        if(strlen($str_dec)<2){
+            return $str;
+        }
+
+        $dim=explode($str_dec[strlen($str_dec)-1],$str_dec);
+
+        for ($i=(count($dim)-2);$i>=1;$i--){
+            if($dim[$i]!=$dim[$i-1]){
+                return $str;
+            }
+        }
+
+        if($dim[0]==$dim[1]){
+            return $dec[0].'.('.$dim[0].$str_dec[strlen($str_dec)-1].')';
+        }else{
+            return $dec[0].'.'.$dim[0].$str_dec[strlen($str_dec)-1].'('.$dim[1].$str_dec[strlen($str_dec)-1].')';
+        }
+    }
+}

hw18/intersection.php

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+<?php
+/**
+ * Definition for a singly-linked list.
+ * class ListNode {
+ *     public $val = 0;
+ *     public $next = null;
+ *     function __construct($val) { $this->val = $val; }
+ * }
+ * Сложность O(n^2)
+ */
+
+class Solution {
+    /**
+     * @param ListNode $headA
+     * @param ListNode $headB
+     * @return ListNode
+     */
+    function getIntersectionNode($headA, $headB) {
+        $nodeA = $headA;
+        $nodeB = $headB;
+        while (is_null($nodeA)===false)
+        {
+            while(is_null($nodeB) === false)
+            {
+                if($nodeA===$nodeB)
+                {
+                    return $nodeA;
+                }
+                $nodeB=$nodeB->next;
+            }
+            $nodeA = $nodeA->next;
+            $nodeB = $headB;
+        }
+        return null;
+    }
+}

hw18/intersection_new.php

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+<?php
+/**
+ * Definition for a singly-linked list.
+ * class ListNode {
+ *     public $val = 0;
+ *     public $next = null;
+ *     function __construct($val) { $this->val = $val; }
+ * }
+ * Сложность O(n^2)
+ */
+
+class Solution {
+    /**
+     * @param ListNode $headA
+     * @param ListNode $headB
+     * @return ListNode
+     */
+    function getIntersectionNode($headA, $headB) {
+        $nodeA = $headA;
+        $nodeB = $headB;
+        while (is_null($nodeA)===false)
+        {
+            while(is_null($nodeB) === false)
+            {
+                if($nodeA===$nodeB)
+                {
+                    return $nodeA;
+                }
+                $nodeB=$nodeB->next;
+            }
+            $nodeA = $nodeA->next;
+            $nodeB = $headB;
+        }
+        return null;
+    }
+}