[알고리즘] K Closest Points to Origin

Problem

 

Key Point

Priority Queue (min heap)

Queue<int[]> priorityQueue = new PriorityQueue<>((a,b) -> (a[0]*a[0]+a[1]*a[1])-(b[0]*b[0]+b[1]*b[1]));

Code

public class KClosest {
    public int[][] solution(int[][] points, int k) {
        int[][] result = new int[k][2];
        Queue<int []> pq = new PriorityQueue<>((a,b) -> (a[0]*a[0]+a[1]*a[1])-(b[0]*b[0]+b[1]*b[1]));
        for (int[] p : points) {
            pq.offer(p);
        }
        System.out.println(pq);
        int index = 0;
        while (index < k) {
            result[index] = pq.poll();
            index++;
        }
        return result;
    }
    public static void main(String[] args) {
        KClosest kClosest = new KClosest();

        int k = 1;
        int[][] points = {{1, 3}, {-2, 2}};
        kClosest.solution(points, k);
    }
}