输入一棵二叉树,判断该二叉树是否是平衡二叉树。
在这里,我们只需要考虑其平衡性,不需要考虑其是不是排序二叉树
public class Solution {
public int TreeDepth(TreeNode root) {
int treeDepth = 0;
if (root == null) {
return treeDepth;
}
if (root.left == null && root.right ==null) {
treeDepth = 1;
return treeDepth;
}
int leftDepth = TreeDepth(root.left);
int rightDepth = TreeDepth(root.right);
return 1 + (leftDepth > rightDepth ? leftDepth : rightDepth);
}
public boolean IsBalanced_Solution(TreeNode root) {
if (root == null) {
return true;
}
if (root.left == null && root.right == null) {
return true;
}
int leftDepth = TreeDepth(root.left);
int rightDepth = TreeDepth(root.right);
if (leftDepth - rightDepth > 1 || rightDepth - leftDepth > 1) {
return false;
}
return IsBalanced_Solution(root.left) && IsBalanced_Solution(root.right);
}
}