feat: add php solution to lcof problem: No.05 (#1009)

Author: Qiu-IT

lcof/面试题05. 替换空格/README.md

@@ -218,6 +218,25 @@ public class Solution {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $s
+     * @return String
+     */
+    function replaceSpace($s) {
+        $rs = "";
+        for ($i = 0; $i < strlen($s); $i++) {
+            if ($s[$i] === " ") $rs = $rs."%20";
+            else $rs = $rs.$s[$i];
+        }
+        return $rs;
+    }
+}
+```
+
 ### **...**
 
 ```

lcof/面试题05. 替换空格/Solution.php

@@ -0,0 +1,14 @@
+class Solution {
+    /**
+     * @param String $s
+     * @return String
+     */
+    function replaceSpace($s) {
+        $rs = "";
+        for ($i = 0; $i < strlen($s); $i++) {
+            if ($s[$i] === " ") $rs = $rs."%20";
+            else $rs = $rs.$s[$i];
+        }
+        return $rs;
+    }
+}