2025-12-13 Daily Challenge

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In: DailyChallenge

Today I have done leetcode's December LeetCoding Challenge with cpp.

December LeetCoding Challenge 13

Description

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.

Solution

class Solution {
  bool validCode(const string &code) {
    if(code.empty()) return false;
    for(auto c : code) {
      if(c != '_' && !isalnum(c)) return false;
    }
    return true;
  }
  bool validBusinessLine(const string &businessLine) {
    return businessLine == "electronics" || businessLine == "grocery" || businessLine == "pharmacy" || businessLine == "restaurant";
  }
public:
  vector<string> validateCoupons(vector<string>& code, vector<string>& businessLine, vector<bool>& isActive) {
    int n = code.size();
    
    vector<int> answerIndice;
    for(int i = 0; i < n; ++i){ 
      if(isActive[i] && validCode(code[i]) && validBusinessLine(businessLine[i])) answerIndice.push_back(i);
    }
    sort(answerIndice.begin(), answerIndice.end(), [&](int a, int b) {
      return businessLine[a] < businessLine[b] || (businessLine[a] == businessLine[b] && code[a] < code[b]);
    });
    vector<string> answer;
    for(auto index : answerIndice) {
      answer.push_back(code[index]);
    }
    return answer;
  }
};

// Accepted
// 779/779 cases passed (4 ms)
// Your runtime beats 69.53 % of cpp submissions
// Your memory usage beats 93.56 % of cpp submissions (66.8 MB)
Algorithm