public int[] findRightInterval(Interval[] intervals) {
if (intervals == null) {
throw new IllegalArgumentException();
}
int len = intervals.length;
int[] result = new int[len];
TreeMap<Integer, Integer> map = new TreeMap<Integer, Integer>();
for (int i = 0; i < len; i++) {
map.put(intervals[i].start, i);
}
for (int i = 0; i < len; i++) {
Integer key = map.ceilingKey(intervals[i].end);
if (key == null) {
result[i] = -1;
} else {
result[i] = map.get(key);
}
}
return result;
}
public List<int[]> getSkyline(int[][] buildings) {
List<int[]> result = new ArrayList<>();
if (buildings == null || buildings.length == 0) {
return result;
}
Comparator<Point> comp =
new Comparator<Point>() {
@Override
public int compare(Point a, Point b) {
if (a.x != b.x) {
return a.x - b.x;
} else {
return a.y - b.y;
}
}
};
PriorityQueue<Point> pq = new PriorityQueue<>(5, comp);
for (int[] data : buildings) {
pq.add(new Point(data[0], -data[2]));
pq.add(new Point(data[1], data[2]));
}
TreeMap<Integer, Integer> map = new TreeMap<>();
map.put(0, 1);
int max = 0;
while (!pq.isEmpty()) {
Point cur = pq.poll();
if (cur.y < 0) {
if (!map.containsKey(-cur.y)) {
map.put(-cur.y, 0);
}
map.put(-cur.y, map.get(-cur.y) + 1);
} else {
map.put(cur.y, map.get(cur.y) - 1);
if (map.get(cur.y) == 0) {
map.remove(cur.y);
}
}
int curMax = map.lastEntry().getKey();
if (curMax != max) {
result.add(new int[] {cur.x, curMax});
max = curMax;
}
}
return result;
}