题目

binary-tree-right-side-now

2. 算法

* queue

3. 代码

class Solution {
public:
    vector<int> rightSideView(TreeNode *root) {
        vector<int> res;
        if (!root) return res;
        queue<TreeNode*> q;
        q.push(root);
        while (!q.empty()) {
            res.push_back(q.back()->val);
            int size = q.size();
            for (int i = 0; i < size; ++i) {
                TreeNode *node = q.front();
                q.pop();
                if (node->left) q.push(node->left);
                if (node->right) q.push(node->right);
            }
        }
        return res;
    }
};