feat: add article for balanced-brackets (#36160)

* feat: add article for balanced-brackets

* fix: reformatted and refactored solution

guide/english/certifications/coding-interview-prep/rosetta-code/balanced-brackets/index.md

@@ -8,3 +8,27 @@ This is a stub. <a href='https://github.com/freecodecamp/guides/tree/master/src/
 <a href='https://github.com/freecodecamp/guides/blob/master/README.md' target='_blank' rel='nofollow'>This quick style guide will help ensure your pull request gets accepted</a>.
 
 <!-- The article goes here, in GitHub-flavored Markdown. Feel free to add YouTube videos, images, and CodePen/JSBin embeds  -->
+
+### Basic Solution
+```js
+function isBalanced(str) {
+  if (str === '') return true;
+
+  str = str.split('');
+  let stack = [];
+  for (let i = 0; i < str.length; i++) {
+    if (str[i] === '[') {
+      stack.push('[');
+    } else if (str[i] === ']' && stack[stack.length - 1] === '[') {
+      stack.pop();
+    }
+  }
+  return stack.length === 0;
+}
+```
+
+#### Code Explanation
+- Split the input string into individual characters & loop over them.
+- Push every `[` into a stack.
+- Check if the item stored on the stack is `[` when a `]` occurs. This makes it a pair & `[` can be removed from the stack.
+- The brackets are balanced if there is no item present in the stack.