🔄 Array.prototype.reverse() Polyfill

The reverse() method reverses an array in place and returns the reference to the same array.

✅ Implementation

Array.prototype.customReverse = function() {
    let left = 0;
    let right = this.length - 1;

    // Swap elements from both ends towards the center
    while (left < right) {
        [this[left], this[right]] = [this[right], this[left]]; // Swap
        left++;
        right--;
    }

    return this; // Return the modified array (reverse is in-place)
};

// Example usage:
const array = ['one', 'two', 'three'];
console.log('array:', array); // Output: ["one", "two", "three"]

const reversed = array.customReverse();
console.log('reversed:', reversed); // Output: ["three", "two", "one"]

// The original array is also reversed since the method modifies it in place
// console.log('array:', array); // Output: ["three", "two", "one"]

Key Features:

• In-place Reversal : The array is reversed directly, modifying the original array.
• Two-pointer Approach : Efficient swapping using two pointers (left and right) that move towards each other.
• Time Complexity : O(n)—each element is swapped once.
• Space Complexity : O(1)—no additional memory is used, other than the variables for the pointers.

This method efficiently reverses the array while mimicking the behavior of the native .reverse() method in JavaScript.