Queue Reconstruction by Height

Suppose you have a random list of people standing in a queue. Each person is described by a pair of integers (h, k), where h is the height of the person and k is the number of people in front of this person who have a height greater than or equal to h. Write an algorithm to reconstruct the queue.

Note: The number of people is less than 1,100.

Example

Input:
[[7,0], [4,4], [7,1], [5,0], [6,1], [5,2]]

Output:
[[5,0], [7,0], [5,2], [6,1], [4,4], [7,1]]

class Solution {
    public int[][] reconstructQueue(int[][] people) {
        // Sorting on descending height followed by ascending by k for same height
        Arrays.sort(people, (a, b) -> a[0] == b[0] ? a[1] - b[1] : b[0] - a[0]);
        ArrayList<int[]> list = new ArrayList<>();
        for (int[] x : people)
            list.add(x[1], x);
        return list.toArray(new int[people.length][]);
    }
}