层次遍历 思路 按照行层次遍历,这算是基本功了。 代码 /* struct TreeNode { int val; struct TreeNode *left; struct TreeNode *right; TreeNode(int x) : val(x), left(NULL), right(NULL) { } }; */ class Solution { public: vector<vector<int> > Print(TreeNode* pRoot) { vector&l...