feat: add php solution to lc problem: No.0557 (doocs#938)

No.0557.Reverse Words in a String III

Author: Qiu-IT

solution/0500-0599/0557.Reverse Words in a String III/README.md

@@ -138,6 +138,24 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $s
+     * @return String
+     */
+    function reverseWords($s) {
+        $sArr = explode(' ', $s);
+        for ($i = 0; $i < count($sArr); $i++) {
+            $sArr[$i] = strrev($sArr[$i]);
+        }
+        return implode(" ", $sArr);
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0500-0599/0557.Reverse Words in a String III/README_EN.md

@@ -121,6 +121,24 @@ impl Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $s
+     * @return String
+     */
+    function reverseWords($s) {
+        $sArr = explode(' ', $s);
+        for ($i = 0; $i < count($sArr); $i++) {
+            $sArr[$i] = strrev($sArr[$i]);
+        }
+        return implode(" ", $sArr);
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0500-0599/0557.Reverse Words in a String III/Solution.php

@@ -0,0 +1,13 @@
+class Solution {
+    /**
+     * @param String $s
+     * @return String
+     */
+    function reverseWords($s) {
+        $sArr = explode(' ', $s);
+        for ($i = 0; $i < count($sArr); $i++) {
+            $sArr[$i] = strrev($sArr[$i]);
+        }
+        return implode(" ", $sArr);
+    }
+}