题解 | #判断是不是平衡二叉树#

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 *	TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 * };
 */
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 pRoot TreeNode类 
     * @return bool布尔型
     */
    int dfs(TreeNode* pRoot, int h)
    {
        if(!pRoot)
            return h;
        return max(dfs(pRoot->left,h+1),dfs(pRoot->right,h+1));
    }

    bool IsBalanced_Solution(TreeNode* pRoot) {
        // write code here
        if(!pRoot)
            return true;

        return (abs(dfs(pRoot->left,0)-dfs(pRoot->right,0))<=1) && IsBalanced_Solution(pRoot->left) && IsBalanced_Solution(pRoot->right);
    }
};