# Binary Tree Right Side View Problem

## Description

LeetCode Problem 199.

Given the root of a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom.

Example 1:

``````1
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Input: root = [1,2,3,null,5,null,4]
Output: [1,3,4]
``````

Example 2:

``````1
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Input: root = [1,null,3]
Output: [1,3]
``````

Example 3:

``````1
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Input: root = []
Output: []
``````

Constraints:

• The number of nodes in the tree is in the range [0, 100].
• -100 <= Node.val <= 100

## Sample C++ Code

``````1
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class Solution {
public:
vector<int> rightSideView(TreeNode* root) {
vector<int> ans;
if (root == NULL)
return ans;
queue<TreeNode*> bfsQ;
bfsQ.push(root);

TreeNode* curr;
int len;
while (!bfsQ.empty()) {
len = bfsQ.size();
for (int i = 0; i < len; i ++) {
curr = bfsQ.front();
bfsQ.pop();
if (curr != NULL) {
if (curr->left != NULL) {
bfsQ.push(curr->left);
}
if (curr->right != NULL) {
bfsQ.push(curr->right);
}
if (i == len - 1) {
ans.push_back(curr->val);
}
}
}
}
return ans;
}
};
``````