LeetCode 662. 二叉树的最大宽度【含空节点】
原题链接
中等
作者:
大明湖的鱼
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2021-01-31 23:08:57
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所有人可见
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阅读 425
有一个数据相当恶心,要用unsigned long long
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode() : val(0), left(nullptr), right(nullptr) {}
* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
* };
*/
class Solution {
public:
int maxW = 0;
int widthOfBinaryTree(TreeNode* root) {
vector<unsigned long long> left;
dfs(root,1,1,left);
return maxW;
}
void dfs(TreeNode* r, int level,unsigned long long index, vector<unsigned long long>& left){
if(r == nullptr) return ;
if(level > left.size()) left.emplace_back(index);
maxW = maxW > (index - left[level-1] +1) ? maxW : (index - left[level-1] +1);
dfs(r->left,level+1,index*2,left);
dfs(r->right,level+1,index*2+1,left);
}
};