题解 | #判断是不是平衡二叉树#

public class Solution {
    public boolean IsBalanced_Solution(TreeNode root) {
        if(root == null){
            return true;
        }
        return isBalanced(root)[0] == 1;
    public int[] isBalanced(TreeNode root){
        if(root == null){
            return new int[]{1,0};
        }
        int[] left = isBalanced(root.left);
        int[] right = isBalanced(root.right);
        if(left[0]==1 && right[0] == 1 && Math.abs(left[1]-right[1])<=1){
            return new int[]{1,Math.max(left[1],right[1])+1};
        }
        return new int[]{0,0};
    }
}