How does JavaScript's `sort()` function actually work behind the scenes?

Understanding JavaScript's sort() Function and its Inner Workings

The built-in sort() function is commonly utilized in JavaScript to arrange arrays in numerical or alphabetical order. This operation is executed through a comparison function provided as an argument to the method.

The code presented compares two numbers (a and b) and returns the following results:

• Less than 0: a is sorted before b.
• Zero: a and b remain in their original positions.
• Greater than 0: b is sorted before a.

Multiple Calls to the Callback Function

The callback function provided to sort() is invoked multiple times throughout the sorting process. The specific pairing of numbers passed into the function varies with each iteration.

You initially предположил that the callback would first handle 25 (a) and 8 (b), followed by 7 (a) and 41 (b). However, this is not the sequence in which the comparisons actually occur.

Here's the breakdown of the steps involved:

• Iteration 1: 25 (a) is compared to 8 (b).
• Iteration 2: 25 (a) is compared to 7 (b).
• Iteration 3: 8 (a) is compared to 7 (b).
• Iteration 4: 25 (a) is compared to 41 (b).

These comparisons result in the following partially sorted array: [8, 7, 25, 41].

Sorting the Partially Sorted Lists

At this point, two unsorted lists remain: [8, 7] and [25, 41]. The algorithm iterates through these lists, sorting them independently.

The final sorted result is [7, 8, 25, 41].

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