KklgOk - Online Python3 Interpreter & Debugging Tool

class Allocator:
    def __init__(self, n: int):
        self.arr = [None] * n

    def allocate(self, size: int, mID: int) -> int:
        index_arr = [-1]
        for i in range(len(self.arr)):
            if self.arr[i] is not None:
                index_arr.append(i)
        index_arr.append(len(self.arr))

        start = -1
        for k in range(len(index_arr) - 1):
            free_len = index_arr[k + 1] - index_arr[k] - 1
            if free_len >= size:
                start = index_arr[k] + 1
                break

        if start == -1:
            return -1

        for x in range(start, start + size):
            self.arr[x] = mID
        return start

    def freeMemory(self, mID: int) -> int:
        cnt = 0
        for i, val in enumerate(self.arr):
            if val == mID:
                self.arr[i] = None
                cnt += 1
        return cnt