1825. Finding MK Average

from sortedcontainers import SortedList


class MKAverage:
    def __init__(self, m: int, k: int):
        self.m = m
        self.k = k
        self.sl = SortedList()
        self.q = deque()
        self.s = 0

    def addElement(self, num: int) -> None:
        self.q.append(num)
        if len(self.q) == self.m:
            self.sl = SortedList(self.q)
            self.s = sum(self.sl[self.k : -self.k])
        elif len(self.q) > self.m:
            i = self.sl.bisect_left(num)
            if i < self.k:
                self.s += self.sl[self.k - 1]
            elif self.k <= i <= self.m - self.k:
                self.s += num
            else:
                self.s += self.sl[self.m - self.k]
            self.sl.add(num)

            x = self.q.popleft()
            i = self.sl.bisect_left(x)
            if i < self.k:
                self.s -= self.sl[self.k]
            elif self.k <= i <= self.m - self.k:
                self.s -= x
            else:
                self.s -= self.sl[self.m - self.k]
            self.sl.remove(x)

    def calculateMKAverage(self) -> int:
        return -1 if len(self.sl) < self.m else self.s // (self.m - self.k * 2)


# Your MKAverage object will be instantiated and called as such:
# obj = MKAverage(m, k)
# obj.addElement(num)
# param_2 = obj.calculateMKAverage()