[프로그래머스 • 코틀린] 로또의 최고 순위와 최저 순위 #77484

#77484

🎄 Question ?

Description

Lotto 6/45(Hereinafter 'Lotto') is a popular lottery game where six numbers are drawn from a pool of 45 numbers. The lottery prize tiers are as follows1:

Prize TiersRequirement

1	All six numbers match
2	Five numbers match
3	Four numbers match
4	Three numbers match
5	Two numbers match
6 (no prize)	All other cases

You bought a lotto ticket and have been waiting for the draw. However, your little brother drew scribbles all over your ticket so that you can't make out some of its numbers. After the draw, you wanted to figure out the highest prize you could have won as well as the lowest prize you could have got.
Suppose that your ticket contained the following set of numbers: 44, 1, 0, 0, 31 25, where 0s represent the numbers on your ticket that you can't make out. If the six winning lottery numbers are 31, 10, 45, 1, 6, and 19, then the following shows the highest and the lowest prize you could have won.

Winning numbers3110451619Result

Highest prize	31	0→10	44	1	0→6	25	four matching numbers, wins the 3rd prize
Lowest prize	31	0→11	44	1	0→7	25	two matching numbers, wins the 5th prize

• The order in which the numbers are drawn is irrelevant.
• Had the numbers you can't make out been 10 and 6, you could have won the 3rd prize.
  • There are other possibilities where you could have won the 3rd prize. However, you would not have won a prize higher than the 3rd one.
• Had the numbers you can't make out been 11 and 7, you could have won the 5th prize.
  • There are other possibilities where you could have won the 5th prize. However, you would not have won any prize (Tier 6).

Suppose parameters lottos and win_nums are given, where lottos is an array containing the numbers on your ticket and win_nums an array containing the winning numbers. Please write a function solution that returns the highest prize tier and the lowest prize tier that you could have won.

Constraints

• lottos is an integer array whose length is 6.
• The elements of lottos are integers between 0 and 45.
  • 0 represents the number you can't make out.
  • Other than 0s, no integers in lottos overlap.
  • The elements of lottos may not be arranged in a certain order.
• win_nums is an integer array whose length is 6.
• The elements of win_nums are integers between 1 and 45.
  • No integers in win_nums will overlap.
  • The elements of win_nums may not be arranged in a certain order.

https://school.programmers.co.kr/learn/courses/30/lessons/77484

🧩 Thought Process

1. lottos의 모든 값을 for문을 돌려 확인 했다.
2. 0을 엘레먼트로 가진 경우에는 max_wins에 1을 더해 주었다. 이 값은 추가적으로 맞출수 있는 값을 말한다.
3. 0이 아닌 경우에는 로또당첨 숫자와 모두 비교를 해주고 같은 숫자가 있으면 fixed_wins에 1을 더해준다.
4. 같은 숫자가 나올 최소 개수는 fixed_wins에 저장된 수일 것이고 최대 개수는 fixed_wins+max_wins일 것이다.
5. 리턴 해야하는 값은 맞춘 로또 개수가 아닌 맞춘 로또 개수에 따른 당첨액 순위이기 때문에 이를 변환해주는 함수를 간단하게 따로 만들어주 었다.

 

🎀 Answer

class Solution {
    fun solution(lottos: IntArray, win_nums: IntArray): IntArray {
        var fixed_wins:Int = 0
        var max_wins:Int = 0
        for (i in lottos.indices) {
            if (lottos[i] == 0) {
                max_wins += 1
            } else {
                for (j in win_nums.indices) {
                    if (lottos[i] == win_nums[j]) {
                        fixed_wins += 1
                    }
                }
            }
            
            
        }
        
        return intArrayOf(prizeTier(fixed_wins+max_wins), prizeTier(fixed_wins))
    }
    
    fun prizeTier(wins: Int):Int {
        return when(wins) {
            6 -> 1
            5 -> 2
            4 -> 3
            3 -> 4
            2 -> 5
            else -> 6
        }
    }
}

 

🎁 Result

🏆 Comment

indices를 사용하면 i가 그 인덱스에 해당하는 엘레먼트 값을 가질 것이라고 착각을 해서 중간에 시간이 걸렸다.

array[i]를 해주어야하고 indices를 사용하면 i 는 인덱스 만을 리턴한 다는 것을 기억해주어야겠다.