Average of Levels in Binary Tree

题意：求每一层的数据平均值，放到Vector里

思路：层序遍历，没啥难的

/** * Definition for a binary tree node. * struct TreeNode { *     int val; *     TreeNode *left; *     TreeNode *right; *     TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */class Solution {public:    vector<double> averageOfLevels(TreeNode* root) {        vector<double> v;        queue<TreeNode*> q;        q.push(root);        while(!q.empty()){            int num = q.size();            double sum = 0;            for(int i = 0;i<num ;i++){                TreeNode* temp = q.front();                q.pop();                sum += temp->val;                if(temp->left!=NULL){                    q.push(temp->left);                }                if(temp->right!=NULL){                    q.push(temp->right);                }                            }            v.push_back(sum/num);        }                return v;    }};