Time Complexity

• Reversing the result list: The result list is reversed at the end to maintain the original order of the elements. This operation takes  time.

We're not reversing anything here. So this bullet point can be removed I guess?

class Solution {
    nextLargerElement(arr) {
        let stack = []; // Initialize an empty stack to store indices of elements
        let res = new Array(arr.length).fill(-1); // Initialize a result array with -1 values

        // Iterate through the input array from right to left
        for (let i = arr.length - 1; i >= 0; i--) {
            while (stack.length && stack[stack.length - 1] <= arr[i]) {
                // While the stack is not empty and the element at the top of the stack
                // is less than or equal to the current element, pop elements from the stack
                stack.pop();
            }

            if (stack.length) {
                // If the stack is not empty after popping, it means the current element
                // has found its next larger element
                res[i] = stack[stack.length - 1];
            }

            // Push the current element's index onto the stack
            stack.push(arr[i]);
        }

        return res; // Return the result array containing the next larger elements
    }
}

// Test cases
let sol = new Solution();
console.log(sol.nextLargerElement([4, 5, 2, 25])); // [5, 25, 25, -1]
console.log(sol.nextLargerElement([13, 7, 6, 12])); // [-1, 12, 12, -1]
console.log(sol.nextLargerElement([1, 2, 3, 4, 5])); // [2, 3, 4, 5, -1]