The Skyline Problem leetcode Java__java

public class Solution {class KeyPoint {public int key;
        public int height;

        Public KeyPoint next = null;
            public KeyPoint (int key, int height) {this.key = key;
        This.height = height;
        } public static int[] Getkeypoint (int key, int height) {int[] kp = new int[2];
        Kp[0] = key;
        KP[1] = height;
    return KP;
        List<int[]> getskyline (int[][] buildings) {KeyPoint head = new KeyPoint ( -1,0);
        KeyPoint PREVKP = head;
            For (int[] building:buildings) {int L = building[0], r = building[1], h= building[2];
            Insert left point while (Prevkp.next!= null && prevKP.next.key <= l) PREVKP = Prevkp.next;
            int preheight = Prevkp.height;
            if (Prevkp.key = = L) prevkp.height = Math.max (Prevkp.height, h); else if (Prevkp.height < h) {KeyPoint next = Prevkp.nexT
                Prevkp.next = new KeyPoint (l, h);
                PREVKP = Prevkp.next;
            Prevkp.next = Next;
            }//Insert right point and update points in between KeyPoint prev = PREVKP, cur = prevkp.next;
                while (cur!= null && Cur.key < r) {preheight = Cur.height;
                Cur.height = Math.max (Cur.height, h);
                if (cur.height = = prev.height) Prev.next = Cur.next;
                else prev = cur;
            cur = cur.next;
                } if (Prev.height!= preheight && prev.key!= r && (cur = null | | Cur.key!= r)) {
                KeyPoint next = Prev.next;
                Prev.next = new KeyPoint (r, Preheight);
            Prev.next.next = Next;
        }//Convert to list<int[]> list<int[]> List = new arraylist<int[]> (); KeyPoint prev =Head, cur = head.next; while (cur!= null) {if (cur.height!= prev.height) list.add (Getkeypoint (Cur.key, Cur.height)
            );
            prev = cur;
        cur = cur.next;
    } return list; }
}