/**

public double[] medianSlidingWindow(int[] nums, int k) {

MyMap up = new MyMap();

MyMap down = new MyMap(Comparator.reverseOrder());

double[] result = new double[nums.length - k + 1];

for (int i = 0; i < nums.length; i++) {

up.myAdd(nums[i]);

down.myAdd(up.myPollFirst());

if (i >= k) {

if (up.containsKey(nums[i - k])) {

up.myRemove(nums[i - k]);

} else {

down.myRemove(nums[i - k]);

}

}

if (up.size < down.size) {

up.myAdd(down.myPollFirst());

}

if (i >= k - 1) {

result[i - k + 1] = up.size == down.size

? ((double) up.firstKey() + down.firstKey()) / 2 : up.firstKey();

}

}

return result;

}

class MyMap extends TreeMap<Integer, Integer> {

int size;

MyMap() {

super();

}

MyMap(Comparator<Integer> comparator) {

super(comparator);

}

void myAdd(int n) {

put(n, getOrDefault(n, 0) + 1);

size++;

}

boolean myRemove(int n) {

int count = getOrDefault(n, 0);

if (count == 0) {

return false;

}

if (count == 1) {

remove(n);

} else {

put(n, count - 1);

}

size--;

return true;

}

int myPollFirst() {

Map.Entry<Integer, Integer> entry = firstEntry();

if (entry.getValue() == 1) {

pollFirstEntry();

} else {

put(entry.getKey(), entry.getValue() - 1);

}

size--;

return entry.getKey();

}

}