def __init__(self, nums):
        """
        initialize your data structure here.
        :type nums: List[int]
        """
        self.ls = len(nums)
        self.tree = [0] * (self.ls * 2)
        self.buildTree(nums)

        initialize your data structure here.
        :type nums: List[int]
        
python/307_Range_Sum_Query_Mutable.py