Java算法中二叉树的练习题有哪些

小编给大家分享一下Java算法中二叉树的练习题有哪些，相信大部分人都还不怎么了解，因此分享这篇文章给大家参考一下，希望大家阅读完这篇文章后大有收获，下面让我们一起去了解一下吧！

题目一

解法

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode() {} *     TreeNode(int val) { this.val = val; } *     TreeNode(int val, TreeNode left, TreeNode right) { *         this.val = val; *         this.left = left; *         this.right = right; *     } * } */class Solution {    int i = 0;    int res = 0;    public int kthSmallest(TreeNode root, int k) {        method(root,k);        return res;    }     public void method(TreeNode root, int k){        if(root==null) return ;        method(root.left,k);        i++;        if(i==k){            res = root.val;            return ;        }        method(root.right,k);     }}

题目二

解法

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode() {} *     TreeNode(int val) { this.val = val; } *     TreeNode(int val, TreeNode left, TreeNode right) { *         this.val = val; *         this.left = left; *         this.right = right; *     } * } */class Solution {    int sum = 0;    public TreeNode convertBST(TreeNode root) {        method(root);        return root;    }    public void method(TreeNode root) {        if(root==null){            return;        }        method(root.right);        sum+=root.val;        root.val = sum;        method(root.left);     }}

题目三

解法

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode() {} *     TreeNode(int val) { this.val = val; } *     TreeNode(int val, TreeNode left, TreeNode right) { *         this.val = val; *         this.left = left; *         this.right = right; *     } * } */class Solution {    public boolean isValidBST(TreeNode root) {        return method(root,null,null);    }    public boolean method(TreeNode root,TreeNode min,TreeNode max){        if(root==null) return true;        if(min!=null&&root.val<=min.val) return false;        if(max!=null&&root.val>=max.val) return false;        return method(root.left,min,root)&&method(root.right,root,max);    }}

题目四

解法

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode() {} *     TreeNode(int val) { this.val = val; } *     TreeNode(int val, TreeNode left, TreeNode right) { *         this.val = val; *         this.left = left; *         this.right = right; *     } * } */class Solution {    public TreeNode searchBST(TreeNode root, int val) {        if(root==null) return null;        if(root.val==val) return root;        if(root.val>=val){            return searchBST(root.left,val);        }        if(root.val
题目五
解法
/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode() {} *     TreeNode(int val) { this.val = val; } *     TreeNode(int val, TreeNode left, TreeNode right) { *         this.val = val; *         this.left = left; *         this.right = right; *     } * } */class Solution {    public TreeNode insertIntoBST(TreeNode root, int val) {        return  method(root,val);    }    public TreeNode method(TreeNode root, int val){        if(root==null) return new TreeNode(val);        if (root.val < val)             root.right = insertIntoBST(root.right, val);        if (root.val > val)             root.left = insertIntoBST(root.left, val);        return root;    }}
题目六
算法
/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode() {} *     TreeNode(int val) { this.val = val; } *     TreeNode(int val, TreeNode left, TreeNode right) { *         this.val = val; *         this.left = left; *         this.right = right; *     } * } */class Solution {    public TreeNode deleteNode(TreeNode root, int key) {        if (root == null) return null;        if (root.val == key){            if (root.left == null) return root.right;            if (root.right == null) return root.left;            TreeNode minNode = getMin(root.right);            root.right = deleteNode(root.right, minNode.val);            minNode.left = root.left;            minNode.right = root.right;            root = minNode;        }else if(root.val>key){            root.left = deleteNode(root.left,key);        }else{            root.right = deleteNode(root.right,key);        }        return root;    }    TreeNode getMin(TreeNode node) {        while (node.left != null) node = node.left;        return node;    }   }
以上是"Java算法中二叉树的练习题有哪些"这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注行业资讯频道！