Added support for arrays and single strings

snippets/longestString.md

@@ -1,16 +1,26 @@
 ### longestString
 
 Takes an array of strings and returns the longest one.
+The method also accepts combinations of single strings and string arrays
 
 Uses the [rest operator](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters)
 to handle arrays as well as an indefinite amount of single arguments.
 Strings are compared using `Array.reduce()`.
 
 ```js
-const longestString = (...strings) => [...strings].reduce((a, b) => a.length > b.length ? a : b);
+const longestString = (...strings) => strings.map(str => {
+                          if (Array.isArray(str)) {
+                            const first = str.shift();
+                            strings.concat(str);
+                            return first;
+                          } else {
+                            return str;
+                          }
+                        }).reduce((a, b) => a.length > b.length ? a : b);
 ```
 
 ```js
-longestString('this', 'is', 'a', 'testcase') // 'testcase'
-longestString(['a', 'ab', 'abc']) // 'abc'
+longestString('this', 'is', 'a', 'testcase'); // 'testcase'
+longestString(['a', 'ab', 'abc']); // 'abc'
+longestString(['a', 'ab', 'abc'], 'abcd'); // 'abcd'
 ```