import java.util.ArrayList;
import java.util.Collections;

public class ArraySort {
    public static void main(String[] args) {
        ArrayList<int[]> arrayListOfPoints = new ArrayList<>();
        arrayListOfPoints.add(new int[] { 6, 6 });
        arrayListOfPoints.add(new int[] { 3, 2 });
        arrayListOfPoints.add(new int[] { 1, 2 });
        Collections.sort(arrayListOfPoints, (a, b) -> Integer.compare(a[0], b[0]));

    }
}