coupon-code-validator

You are given three arrays of length n that describe the properties of n coupons: code, businessLine, and isActive. The ith coupon has:

• code[i]: a string representing the coupon identifier.


• businessLine[i]: a string denoting the business category of the coupon.


• isActive[i]: a boolean indicating whether the coupon is currently active.

A coupon is considered valid if all of the following conditions hold:

1. code[i] is non-empty and consists only of alphanumeric characters (a-z, A-Z, 0-9) and underscores (_).


2. businessLine[i] is one of the following four categories: "electronics", "grocery", "pharmacy", "restaurant".


3. isActive[i] is true.

Return an array of the codes of all valid coupons, sorted first by their businessLine in the order: "electronics", "grocery", "pharmacy", "restaurant", and then by code in lexicographical (ascending) order within each category.

Example 1:

Input: code = ["SAVE20","","PHARMA5","SAVE@20"], businessLine = ["restaurant","grocery","pharmacy","restaurant"], isActive = [true,true,true,true]

Output: ["PHARMA5","SAVE20"]

Explanation:

• First coupon is valid.


• Second coupon has empty code (invalid).


• Third coupon is valid.


• Fourth coupon has special character @ (invalid).

Example 2:

Input: code = ["GROCERY15","ELECTRONICS_50","DISCOUNT10"], businessLine = ["grocery","electronics","invalid"], isActive = [false,true,true]

Output: ["ELECTRONICS_50"]

Explanation:

• First coupon is inactive (invalid).


• Second coupon is valid.


• Third coupon has invalid business line (invalid).

Constraints:

• n == code.length == businessLine.length == isActive.length


• 1 <= n <= 100


• 0 <= code[i].length, businessLine[i].length <= 100


• code[i] and businessLine[i] consist of printable ASCII characters.


• isActive[i] is either true or false.