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‎LeetCode/678_javascript.js‎

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// 给定一个只包含三种字符的字符串：（ ，） 和 *，写一个函数来检验这个字符串是否为有效字符串。有效字符串具有如下规则：
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// 任何左括号 ( 必须有相应的右括号 )。
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// 任何右括号 ) 必须有相应的左括号 ( 。
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// 左括号 ( 必须在对应的右括号之前 )。
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// * 可以被视为单个右括号 ) ，或单个左括号 ( ，或一个空字符串。
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// 一个空字符串也被视为有效字符串。
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// 示例 1:
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// 输入: "()"
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// 输出: True
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// 示例 2:
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// 输入: "(*)"
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// 输出: True
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// 示例 3:
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// 输入: "(*))"
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// 输出: True
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// 注意:
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// 字符串大小将在 [1，100] 范围内。
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/**
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* @param {string} s
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* @return {boolean}
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*/
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// 2021.09.12 每日一题
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// 使用栈
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var checkValidString = function (s) {
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// 分别记录左括号和* 的剩余
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let left = [];
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let asterisk = [];
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for (let i = 0; i < s.length; i++) {
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if (s[i] == "(") {
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left.push(i);
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} else if (s[i] == ")") {
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// 匹配右括号 左括号减一
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// 或者 星号数量减一
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if (left.length) {
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left.pop();
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} else if (asterisk.length) {
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asterisk.pop();
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} else {
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return false;
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}
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} else {
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asterisk.push(i);
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}
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}
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while (left.length && asterisk.length) {
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let l = left.pop();
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let ast = asterisk.pop();
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// 需保证 left 内元素 在星号元素左边
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if (l > ast) {
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return false;
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}
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}
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return left.length == 0;
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};
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// 贪心可以优化空间复杂度
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// 待定

‎README.md‎

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| 611 | [有效三角形的个数](./LeetCode/611_typescript.ts) | [Valid Triangle Number](https://leetcode-cn.com/problems/valid-triangle-number/) | typescript, | 贪心算法 | medium |
203203
| 633 | [平方数之和](./LeetCode/633_javascript.js) | [Sum Of Square Numbers](https://leetcode-cn.com/problems/sum-of-square-numbers/) | javascript, | 双指针 | medium |
204204
| 671 | [二叉树中第二小的节点](./LeetCode/671_javascript.js) | [Second Minimum Node In a Binary Tree](https://leetcode-cn.com/problems/second-minimum-node-in-a-binary-tree/) | javascript, | 回溯,递归, BFS,DFS,树 | eazy | |
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| 678\* | [有效的括号字符串](./LeetCode/678_javascript.js) | [Valid Parenthesis String](https://leetcode-cn.com/problems/valid-parenthesis-string/) | javascript, | 贪心#,动态规划#,栈 | medium |
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| 680 | [验证回文字符串 II](./LeetCode/680_javascript.js) | [Valid Palindrome II](https://leetcode-cn.com/problems/valid-palindrome-ii/) | javascript, | 双指针 | eazy |
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| 690 | [图像渲染](./LeetCode/690_javascript.js) | [Employee Importance](https://leetcode-cn.com/problems/employee-importance/) | javascript, | 回溯,递归, BFS,DFS | medium |
207208
| 692 | [前 K 个高频单词](./LeetCode/692_javascript.js) | [Top K Frequent Words](https://leetcode-cn.com/problems/top-k-frequent-words/) | javascript, | 哈希 | medium |
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| 516 | [最长回文子序列](./LeetCode/516_javascript.js) | [Longest Palindromic Subsequence](https://leetcode-cn.com/problems/longest-palindromic-subsequence/) | javascript, | 动态规划 | medium |
334335
| 518 | [零钱兑换 II](./LeetCode/518_javascript.js) | [Coin Change 2](https://leetcode-cn.com/problems/coin-change-2/) | javascript, | 动态规划,DFS | medium |
335336
| 552 | [学生出勤记录 II](./LeetCode/552_javascript.js) | [Student Attendance Record II](https://leetcode-cn.com/problems/student-attendance-record-ii/) | javascript, | 动态规划 | hard |
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| 678 | [有效的括号字符串](./LeetCode/678_javascript.js) | [Valid Parenthesis String](https://leetcode-cn.com/problems/valid-parenthesis-string/) | javascript, | 贪心#,动态规划#,栈 | medium |
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| 704 | [二分查找](./LeetCode/704_javascript.js) | [Binary Search](https://leetcode-cn.com/problems/binary-search/) | javascript, | 二分 | eazy |
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| 714 | [买卖股票的最佳时机含手续费](./LeetCode/714_javascript.js) | [Best Time to Buy and Sell Stock with Transaction Fee](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee/) | javascript, | 动态规划 | medium |
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| 746 | [使用最小花费爬楼梯](./LeetCode/746_javascript.js) | [min Cost Climbing Stairs](https://leetcode-cn.com/problems/min-cost-climbing-stairs/) | javascript, | 动态规划 | eazy |
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| 581 | [最短无序连续子数组](./LeetCode/581_javascript.js) | [Shortest Unsorted Continuous Subarray](https://leetcode-cn.com/problems/shortest-unsorted-continuous-subarray/) | javascript, | 贪心算法 | medium |
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| 605 | [种花问题](./LeetCode/787_javascript.js) | [Can Place Flowers](https://leetcode-cn.com/problems/can-place-flowers/) | javascript, | 贪心算法 | eazy |
439441
| 611 | [有效三角形的个数](./LeetCode/611_typescript.ts) | [Valid Triangle Number](https://leetcode-cn.com/problems/valid-triangle-number/) | typescript, | 贪心算法 | medium |
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| 678 | [有效的括号字符串](./LeetCode/678_javascript.js) | [Valid Parenthesis String](https://leetcode-cn.com/problems/valid-parenthesis-string/) | javascript, | 贪心#,动态规划#,栈 | medium |
440443
| 763 | [划分字母区间](./LeetCode/787_javascript.js) | [Partition Labels](https://leetcode-cn.com/problems/partition-labels/) | javascript, | 哈希表,贪心算法 | medium |
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| 787 | [K 站中转内最便宜的航班](./LeetCode/787_javascript.js) | [Cheapest Flights Within K Stops](https://leetcode-cn.com/problems/cheapest-flights-within-k-stops/) | javascript, | 回溯,递归 ,动态规划 ,贪心算法 | medium |
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| 789 | [逃脱阻碍者](./LeetCode/789_javascript.js) | [Escape The Ghosts](https://leetcode-cn.com/problems/escape-the-ghosts/) | javascript, | 贪心 | medium |
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650653
---
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### 堆(优先队列)
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### 堆(优先队列 栈
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| # | 题名 | Topic Name | Solution | Keywords | Difficulty | Similar Topics |
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| --- | ----------------------------------- | -------------------------------------------- | :---------- | :----------- | :--------: | :------------: |
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| 502 | [IPO](./LeetCode/502_javascript.js) | [IPO](https://leetcode-cn.com/problems/ipo/) | javascript, | 堆(优先队列) | hard |
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| # | 题名 | Topic Name | Solution | Keywords | Difficulty | Similar Topics |
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| --- | ------------------------------------------------ | -------------------------------------------------------------------------------------- | :---------- | :----------------- | :--------: | :------------: |
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| 502 | [IPO](./LeetCode/502_javascript.js) | [IPO](https://leetcode-cn.com/problems/ipo/) | javascript, | 堆(优先队列) | hard |
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| 678 | [有效的括号字符串](./LeetCode/678_javascript.js) | [Valid Parenthesis String](https://leetcode-cn.com/problems/valid-parenthesis-string/) | javascript, | 贪心#,动态规划#,栈 | medium |
657661

658662
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