---
description: Add super-simple line-by-line comments to a LeetCode solution file
---

Add beginner-level line-by-line comments to the LeetCode solution file at: $1

## Rules

1. **Read the file first.** It follows the standard on-disk format:
   - A `/* ... */` header block containing problem number, title, difficulty, URL, description, examples, and constraints
   - A JSDoc `@param`/`@return` block
   - The solution function(s)

2. **Never touch the header block or JSDoc block.** Preserve them byte-for-byte.

3. **Never change the code.** Do not rename variables, reformat logic, alter whitespace inside expressions, or "improve" anything. Comments only. The file must produce an identical AST after your edit.

4. **Comment style — explain as if to a complete beginner who has never programmed:**
   - One comment line (or short block) ABOVE each meaningful line/statement
   - Use plain everyday language and physical metaphors:
     - object/map → "box" ("Create an empty box to count how many times each number appears")
     - increment → "add 1 to its count"
     - `(freq[x] || 0) + 1` → "If we already saw this number, add 1 to its count. If we never saw it before, start counting from 1"
     - sort comparator → spell out the rule in words ("put the letter that appears MORE times first; if tied, alphabetical order")
     - return → say WHAT is being returned and WHY in plain words
   - Explain the WHY, not just the WHAT ("so the next bigger numbers know there are more smaller ones")
   - Inline comments (`// ...` at end of line) are fine for short trailing clarifications like `.join('')` → "glue the sorted letters back into a string"
   - No jargon without immediate translation: if you must say "index", follow with "(its position)"

5. **Add a section banner** above the solution function in this exact style:
   ```js
   // ============================================
   // <problem number>. <problem title>
   // ============================================
   ```
   Pull the number and title from the header block.

6. **Multiple solutions in one file:** comment every one of them, each with its own banner (append "– Approach 2" etc. to the banner title).

7. **Extra instructions** (if provided after the file path): $@

8. **After editing**, print a one-line confirmation: file path + number of comment lines added. Nothing else.

## Example transformation

Input body:
```js
var smallerNumbersThanCurrent = function (nums) {
  const freq = {};
  for (let x of nums) freq[x] = (freq[x] || 0) + 1;
  return nums.map((x) => smaller[x]);
};
```

Output body:
```js
// ============================================
// 1365. How Many Numbers Are Smaller Than the Current Number
// ============================================

var smallerNumbersThanCurrent = function (nums) {
  // Create an empty box to store how many times each number appears
  const freq = {};

  // Go through every number in the list one by one
  // If we already saw this number, add 1 to its count
  // If we never saw it before, start counting from 1
  for (let x of nums) freq[x] = (freq[x] || 0) + 1;

  // Go through the original list and replace each number
  // with "how many numbers are smaller than it"
  return nums.map((x) => smaller[x]);
};
```