Add solution using RegExp (#34294)

guide/english/certifications/javascript-algorithms-and-data-structures/basic-algorithm-scripting/confirm-the-ending/index.md

@@ -33,3 +33,31 @@ confirmEnding("He has to give me a new name", "name");
 
 ### Relevant Links
  - [String.prototype.slice()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/slice)
+
+
+# ![:rotating_light:](https://forum.freecodecamp.com/images/emoji/emoji_one/rotating_light.png?v=3 ":rotating_light:")Advanced Code Solution:
+ (using Regular Expression)
+ 
+ ```javascript
+function confirmEnding(str, target) {
+  // "Never give up and good luck will find you."
+  // -- Falcor
+  
+  let re = new RegExp(target+'$','i');
+  
+  return re.test(str);
+}
+
+console.log(confirmEnding("Bastian", "n"));
+```
+
+## Code Explanation:
+ - We need to make a pattern from the `target` variable that exists at the end of the string `str`.
+ - Since we will use a variable that will change the pattern each time the function is called, we will use the constructor of the regular expression object `new RegExp(pattern[, flags])`, so we start with: `new RegExp(target)`.
+ - Then we have to check at the end of the string, so we concatenate to the `target` variable the `$` character to match the end: `new RegExp(target+'$')`.
+ - We use the flag `i` to ignore the case of the pattern and we have our completed RegExp: `new RegExp(target+'$','i')`, or we can ommit the flag entirely.
+ - Finally, we are using our regular expression with the `test` method to the given string, to check if the string ends with the pattern and return true or false accordingly.
+ 
+ ### Relevant Links
+  - [RegExp](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp)
+  - [RegExp.prototype.test()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/test)