一棵空树或它的任意节点的左右两个子树的高度差的绝对值均不超过1。
/**
* Definition for binary tree
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
bool isBalanced(TreeNode *root) {
if(root==NULL){
return true;
}
bool isbalance=false;
int ldepth=getdepth(root->left);
int rdepth=getdepth(root->right);
if(abs(ldepth-rdepth)<=1){
isbalance=true;
}
return isbalance&&isBalanced(root->left)&&isBalanced(root->right);
}
int getdepth(TreeNode *root){
if(root==NULL){
return 0;
}
int left=getdepth(root->left);
int right=getdepth(root->right);
return max(left,right)+1;
}
};