Add php solution to lc problems:No.0002,0003

solution/0000-0099/0002.Add Two Numbers/README.md

@@ -432,6 +432,59 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+/**
+ * Definition for a singly-linked list.
+ * class ListNode {
+ *     public $val = 0;
+ *     public $next = null;
+ *     function __construct($val = 0, $next = null) {
+ *         $this->val = $val;
+ *         $this->next = $next;
+ *     }
+ * }
+ */
+class Solution {
+
+    /**
+     * @param ListNode $l1
+     * @param ListNode $l2
+     * @return ListNode
+     */
+    function addTwoNumbers($l1, $l2) {
+        $dummy = new ListNode(0);
+        $current = $dummy;
+        $carry = 0;
+
+        while ($l1 !== null || $l2 !== null) {
+            $x = ($l1 !== null) ? $l1->val : 0;
+            $y = ($l2 !== null) ? $l2->val : 0;
+
+            $sum = $x + $y + $carry;
+            $carry = (int) ($sum / 10);
+            $current->next = new ListNode($sum % 10);
+            $current = $current->next;
+
+            if ($l1 !== null) {
+                $l1 = $l1->next;
+            }
+
+            if ($l2 !== null) {
+                $l2 = $l2->next;
+            }
+        }
+
+        if ($carry > 0) {
+            $current->next = new ListNode($carry);
+        }
+
+        return $dummy->next;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0002.Add Two Numbers/README_EN.md

@@ -420,6 +420,59 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+/**
+ * Definition for a singly-linked list.
+ * class ListNode {
+ *     public $val = 0;
+ *     public $next = null;
+ *     function __construct($val = 0, $next = null) {
+ *         $this->val = $val;
+ *         $this->next = $next;
+ *     }
+ * }
+ */
+class Solution {
+
+    /**
+     * @param ListNode $l1
+     * @param ListNode $l2
+     * @return ListNode
+     */
+    function addTwoNumbers($l1, $l2) {
+        $dummy = new ListNode(0);
+        $current = $dummy;
+        $carry = 0;
+
+        while ($l1 !== null || $l2 !== null) {
+            $x = ($l1 !== null) ? $l1->val : 0;
+            $y = ($l2 !== null) ? $l2->val : 0;
+
+            $sum = $x + $y + $carry;
+            $carry = (int) ($sum / 10);
+            $current->next = new ListNode($sum % 10);
+            $current = $current->next;
+
+            if ($l1 !== null) {
+                $l1 = $l1->next;
+            }
+
+            if ($l2 !== null) {
+                $l2 = $l2->next;
+            }
+        }
+
+        if ($carry > 0) {
+            $current->next = new ListNode($carry);
+        }
+
+        return $dummy->next;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0002.Add Two Numbers/Solution.php

@@ -0,0 +1,49 @@
+<?php
+/**
+ * Definition for a singly-linked list.
+ * class ListNode {
+ *     public $val = 0;
+ *     public $next = null;
+ *     function __construct($val = 0, $next = null) {
+ *         $this->val = $val;
+ *         $this->next = $next;
+ *     }
+ * }
+ */
+class Solution {
+
+    /**
+     * @param ListNode $l1
+     * @param ListNode $l2
+     * @return ListNode
+     */
+    function addTwoNumbers($l1, $l2) {
+        $dummy = new ListNode(0);
+        $current = $dummy;
+        $carry = 0;
+
+        while ($l1 !== null || $l2 !== null) {
+            $x = ($l1 !== null) ? $l1->val : 0;
+            $y = ($l2 !== null) ? $l2->val : 0;
+
+            $sum = $x + $y + $carry;
+            $carry = (int) ($sum / 10);
+            $current->next = new ListNode($sum % 10);
+            $current = $current->next;
+
+            if ($l1 !== null) {
+                $l1 = $l1->next;
+            }
+
+            if ($l2 !== null) {
+                $l2 = $l2->next;
+            }
+        }
+
+        if ($carry > 0) {
+            $current->next = new ListNode($carry);
+        }
+
+        return $dummy->next;
+    }
+}

solution/0000-0099/0003.Longest Substring Without Repeating Characters/README.md

@@ -349,6 +349,35 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $s
+     * @return Integer
+     */
+    function lengthOfLongestSubstring($s) {
+        $max = 0;
+        for ($i = 0; $i < strlen($s); $i++) {
+            $chars = array();
+            $sub = '';
+            for ($j = $i; $j < strlen($s); $j++) {
+                if (in_array($s[$j], $chars)) {
+                    break;
+                }
+                $sub .= $s[$j];
+                $chars[] = $s[$j];
+            }
+            if (strlen($sub) > $max) {
+                $max = strlen($sub);
+            }
+        }
+        return $max;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0003.Longest Substring Without Repeating Characters/README_EN.md

@@ -339,6 +339,35 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $s
+     * @return Integer
+     */
+    function lengthOfLongestSubstring($s) {
+        $max = 0;
+        for ($i = 0; $i < strlen($s); $i++) {
+            $chars = array();
+            $sub = '';
+            for ($j = $i; $j < strlen($s); $j++) {
+                if (in_array($s[$j], $chars)) {
+                    break;
+                }
+                $sub .= $s[$j];
+                $chars[] = $s[$j];
+            }
+            if (strlen($sub) > $max) {
+                $max = strlen($sub);
+            }
+        }
+        return $max;
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0003.Longest Substring Without Repeating Characters/Solution.php

@@ -0,0 +1,25 @@
+<?php
+class Solution {
+    /**
+     * @param String $s
+     * @return Integer
+     */
+    function lengthOfLongestSubstring($s) {
+        $max = 0;
+        for ($i = 0; $i < strlen($s); $i++) {
+            $chars = array();
+            $sub = '';
+            for ($j = $i; $j < strlen($s); $j++) {
+                if (in_array($s[$j], $chars)) {
+                    break;
+                }
+                $sub .= $s[$j];
+                $chars[] = $s[$j];
+            }
+            if (strlen($sub) > $max) {
+                $max = strlen($sub);
+            }
+        }
+        return $max;
+    }
+}