LeetCode 力扣官方题解 | 449. 序列化和反序列化二叉搜索树 449. 序列化和反序列化二叉搜索树题目描述难易度:中等序列化是将数据结构或对象转换为一系列位的过程,以便它可以存储在文件或内存缓冲区中,或通过网络连接链路传输,以便稍后在同一个或另一个计算机环境中重… 阅读全文 赞同 6 添加评论 分享
Thought Process This is an easy problem but might be a bit hard to code it up correctly in one pass. We can use a sliding window to keep a rolling sum and compare it with upper and lower bound. A few caveats in implementation: We can simplify using two pointers start and end by kee...
At first, I am puzzled why this problem would be a hard one. It seems simply applying a BFS would get the answer. So here we go. Brute force, simple BFS Of course it will hit memory limit because I am allocating a 2-dimensional visited array. Assume boolean is 8 bit -> 1B, 1 ...
简介:【leetcode报错】 leetcode格式问题解决:error: stray ‘\302’ in program [solution.c] 一、情景再现 二、报错原因 该错误是指源程序中有非法字符,需要将非法字符去掉。 一般是由于coder1.使用中文输入法或者2.从别的地方直接复制粘贴代码造成的。 代码中出现了中文空格,中文引号,各种中文标点符号都会出现,...
class Solution { public: int candy(vector<int>& ratings) { } }; 1. 2. 3. 4. 5. 6. 7. 思路 这一题运用贪心策略就能写出来,只需要我们进行两次遍历即可。 首先从左向右,如果右边孩子的评分比左边高,则右边孩子的糖果数更新为左边孩子的糖果数加 1; ...
class Solution {//这个方法是判断是否为运算符的 private boolean isOperation(String x) {if(x.equals("+") || x.equals("-") || x.equals("*") || x.equals("/")) {return true; } return false; } public int evalRPN(String[] tokens) {Stack stack = new Stack(); ...
Problem: Solve a given equation and return the value of x in the form of string “x=#value”. The equation contains only ‘+’, ‘-’ operation, the variable x and its coefficient. If there is no solution for the equation, return “No solution”. If there are infinite solutions for ...
Hi, I need help understanding this question solution. The problem is https://leetcode.com/problems/find-the-minimum-cost-array-permutation/ Basically we are given a permutation of 0 to n and have to construct another permutation resres that minimizes the function: ∑n−1i=0∣∣res[i]...
leetcode-cn.com/problem You are given an integer array nums and an integer target. You want to build an expression out of nums by adding one of the symbols '+' and '-' before each integer in nums and then concatenate all the integers. For example, if nums = [2, 1], you can add...
挣扎了一段时间,就去讨论区看解答(https://leetcode.com/problems/strong-password-checker/discuss/91003/O(n%29-java-solution-by-analyzing-changes-allowed-to-fix-each-problem)去了: 代码语言:javascript 代码运行次数:0 运行 复制 class Solution { public int strongPasswordChecker(String s) { int res...