Binary Tree Pruning
给一个二叉树, 求删除值为0并且左右两边都是nullptr的分支.
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/** * 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: TreeNode* pruneTree(TreeNode* root) { if(!root) return root; root->left = pruneTree(root->left); root->right = pruneTree(root->right); if(!root->val && !root->left && !root->right) return nullptr; else return root; } }; |