leetcode1302

class Solution:
    def levelOrder(self,root,l,res):
        while len(l) > 0:
            temp = []
            while len(l) > 0:
                cur = l.pop()
                if cur.left != None:
                    temp.append(cur.left)
                if cur.right != None:
                    temp.append(cur.right)
            if len(temp) > 0:
                l = temp[:]
                res.clear()
                for t in range(len(temp)):
                    res.append(temp[t].val)
                
        
    def deepestLeavesSum(self, root: 'TreeNode') -> int:
        if root == None:
            return 0
        l = [root]
        res = [root.val]
        self.levelOrder(root,l,res)
        sums = 0
        for i in range(len(res)):
            sums += res[i]
        return sums

算法思想：二叉树层次遍历。