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;
}
};