题目

Leetcode 662. 二叉树最大宽度

代码（9.30 首刷看解析）

class Solution {
public:int widthOfBinaryTree(TreeNode* root) {unsigned long long res = 1;using pr = pair<TreeNode*, unsigned long long>;vector<pr> arr;arr.emplace_back(root, 1);while(!arr.empty()) {vector<pr> tmp;for(auto& [node, index] : arr) {if(node->left)tmp.emplace_back(node->left, index*2);if(node->right)tmp.emplace_back(node->right, index*2+1);}res = max(res, arr.back().second - arr[0].second + 1);arr = move(tmp);}return res;}
};