給定一棵二叉樹,想象自己站在它的右側,按照從頂部到底部的順序,返回從右側所能看到的節點值
簡要題解:
二叉樹進行層序遍歷 輸出每層最後一個節點即可。
/**
* 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<int> rightSideView(TreeNode* root) {
vector<int>ans;if(root==NULL) return ans;
queue<TreeNode*>q;
q.push(root); //ans.push_back(root->val);
while(!q.empty())
{ vector<int>tem;
int siz=q.size();
for(int i=0;i<siz;i++)
{
TreeNode* t=q.front();
q.pop();
tem.push_back(t->val);
if(t->left)
q.push(t->left);
if(t->right)
q.push(t->right);
}
int z=tem[siz-1];
ans.push_back(z);
}
return ans;
}
};