题解 | #动物牛树#

常规平衡树

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 *	TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 * };
 */
#include <cctype>
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param root TreeNode类 
     * @return bool布尔型
     */
    int deep(TreeNode* root){
        if (root==nullptr) {
            return 0;
        }
        int left=deep(root->left);
        int right=deep(root->right);
        return left>right?left+1:right+1;
    }
    bool isBalanced(TreeNode* root) {
        // write code here
        if (root==nullptr) {
            return true;
        }
        int left=deep(root->left);
        int right=deep(root->right);
        if(abs(left-right)>1) return false;
        return isBalanced(root->left) && isBalanced(root->right);
    }
};