每日一题 剑指offer（二叉树镜像）

struct TreeNode {
  int val;
  struct TreeNode *left;
  struct TreeNode *right;
  TreeNode(int x) :
      val(x), left(NULL), right(NULL) {
  }
};

class Solution {
public:
    void Mirror(TreeNode *pRoot) {
        if (!pRoot) 
        {
            return;
        }
        vector<TreeNode*> vv;
        vv.push_back(pRoot);
        while (!vv.empty()) {
            vector<TreeNode*> t;
            for (auto &i : vv) {
                swap(i->left, i->right);
                if (i->left)
                {
                    t.push_back(i->left);
                }
                if (i->right) 
                {
                    t.push_back(i->right);
                }
            }
            vv.swap(t);
        }
    }
};