Leetcode 110.Balanced binary tree (balanced binary trees) thinking and method of solving problems

Given a binary tree, determine if it is height-balanced.

For this problem, a height-balanced binary tree was defined as a binary tree in which the depth of the Every node never differ by more than 1.

Idea: Judging whether it is a balanced binary tree, DFS can, recursively determine whether each sub-tree is balanced binary tree, if there are sub-tree is not satisfied, the whole is not satisfied.

The specific code is as follows:

/** * Definition for a binary tree node.  * public class TreeNode {*     int val, *     TreeNode left, *     TreeNode right; *     TreeNode (int x) {val = x;} *} */public class Solution {    /**     * Determine if the binary tree is balanced     * see if the height difference between the left and right subtree is more than 1     * not more than 1 respectively determine whether the left and right sub-tree balance binary tree     */Public Boolean isbalanced (TreeNode root) {        if (root = null)            return true;        if (DEP (0,root) >-Ten)        return true;        return false;    }    Height of the calculation tree    private int dep (int dep,treenode root) {        if (root = null) {            return dep-1;        }        int dep1 = DEP (dep+1,root.left);        int DEP2 = DEP (dep+1,root.right);        If the height difference exceeds 1, return -10        //The subsequent DEP return value will be -10        if (Math.Abs (DEP1-DEP2) > 1) {        return-10;        }        Return dep1 > Dep2? DEP1:DEP2;}    }

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Leetcode 110.Balanced binary tree (balanced binary trees) ideas and methods of solving problems