lc 399 Evaluate Division 399 Evaluate Division Equations are given in the format A / B = k, where A and B are variables represented as strings, and k is a real number (floating point number). Given some queries, return the answers. If the answer does…

Equations are given in the format A / B = k, where A and B are variables represented as strings, and k is a real number (floating point number). Given some queries, return the answers. If the answer does not exist, return -1.0. Example:Given a / b =…

我是链接 看到这道题,2个点和一个权值,然后想到图,但是leetcode就是这样,没给数据范围,感觉写起来很费劲,然后就开始用图来做,添加边的时候,注意正向边和反向变,然后查询的时候,先判断2个点是否都出现,然后判断是不是自己到自己,最后用dfs或者bfs到图里面去搜索,第一次交的时候,忘记用vis标记访问过的点,导致tle,加上之后,就ac了,套路一般吧,不知道还有什么trick. double dfs(vector<vector<pair<int, double> > &…

Evaluate Division题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/evaluate-division/description/ Description Equations are given in the format A / B = k, where A and B are variables represented as strings, and k is a real number (floating point number…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址:https://leetcode.com/problems/delete-and-earn/description/ 题目描述 Equations are given in the format A / B = k, where A and B are variables represented as strings, and k i…

题目如下: Equations are given in the format A / B = k, whereA and B are variables represented as strings, and k is a real number (floating point number). Given some queries, return the answers. If the answer does not exist, return -1.0. Example:Given a /…

图像题,没觉得有什么简单的办法,貌似可以用Union Find来解. 感觉有2种思路,一种是先全部构建好每2个点的weight,然后直接遍历queires[][]来抓取答案. 一种是只构建简单的关系图,然后通过DFS来一一找寻要求的答案. 做了一会好他妈的麻烦,最后参考了(http://blog.csdn.net/yeqiuzs/article/details/52506433) 用的是第二种. 需要注意,不存在 优先于 相等 eg : x/x = -1.0, not 1.0, if x DNE…

Equations are given in the format A / B = k, where A and B are variables represented as strings, and k is a real number (floating point number). Given some queries, return the answers. If the answer does not exist, return -1.0. Example:Given a / b =…

Equations are given in the format A / B = k, where A and B are variables represented as strings, and k is a real number (floating point number). Given some queries, return the answers. If the answer does not exist, return -1.0. Example: Given a / b =…

Evaluate the value of an arithmetic expression in Reverse Polish Notation. Valid operators are +, -, *, /. Each operand may be an integer or another expression. Note: Division between two integers should truncate toward zero. The given RPN expression…