399 - Evaluate Division\.

Medium

You are given an array of variable pairs equations and an array of real numbers values, where <code>equationsi = A_i, B_i</code> and values[i] represent the equation <code>A_i / B_i = valuesi</code>. Each <code>A_i</code> or <code>B_i</code> is a string that represents a single variable.

You are also given some queries, where <code>queriesj = C_j, D_j</code> represents the <code>j^th</code> query where you must find the answer for <code>C_j / D_j = ?</code>.

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

• <code>1 <= A_i.length, B_i.length <= 5</code>

• values.length == equations.length

• 0.0 < values[i] <= 20.0

• 1 <= queries.length <= 20

• queries[i].length == 2

• <code>1 <= C_j.length, D_j.length <= 5</code>

• <code>A_i, B_i, C_j, D_j</code> consist of lower case English letters and digits.