g0301_0400.s0399_evaluate_division.readme.md Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of leetcode-in-java Show documentation
Show all versions of leetcode-in-java Show documentation
Java-based LeetCode algorithm problem solutions, regularly updated
399\. Evaluate Division
Medium
You are given an array of variable pairs `equations` and an array of real numbers `values`, where equations[i] = [Ai, Bi] and `values[i]` represent the equation Ai / Bi = values[i]. Each Ai or Bi is a string that represents a single variable.
You are also given some `queries`, where queries[j] = [Cj, Dj] represents the jth query where you must find the answer for Cj / Dj = ?.
Return _the answers to all queries_. If a single answer cannot be determined, return `-1.0`.
**Note:** The input is always valid. You may assume that evaluating the queries will not result in division by zero and that there is no contradiction.
**Example 1:**
**Input:** equations = [["a","b"],["b","c"]], values = [2.0,3.0], queries = [["a","c"],["b","a"],["a","e"],["a","a"],["x","x"]]
**Output:** [6.00000,0.50000,-1.00000,1.00000,-1.00000]
**Explanation:**
Given: _a / b = 2.0_, _b / c = 3.0_
queries are: _a / c = ?_, _b / a = ?_, _a / e = ?_, _a / a = ?_, _x / x = ?_
return: [6.0, 0.5, -1.0, 1.0, -1.0 ]
**Example 2:**
**Input:** equations = [["a","b"],["b","c"],["bc","cd"]], values = [1.5,2.5,5.0], queries = [["a","c"],["c","b"],["bc","cd"],["cd","bc"]]
**Output:** [3.75000,0.40000,5.00000,0.20000]
**Example 3:**
**Input:** equations = [["a","b"]], values = [0.5], queries = [["a","b"],["b","a"],["a","c"],["x","y"]]
**Output:** [0.50000,2.00000,-1.00000,-1.00000]
**Constraints:**
* `1 <= equations.length <= 20`
* `equations[i].length == 2`
* 1 <= Ai.length, Bi.length <= 5
* `values.length == equations.length`
* `0.0 < values[i] <= 20.0`
* `1 <= queries.length <= 20`
* `queries[i].length == 2`
* 1 <= Cj.length, Dj.length <= 5
* Ai, Bi, Cj, Dj consist of lower case English letters and digits.