Level1_실패율 (C++) (JAVA)

코딩테스트 연습 - 실패율

 

[C++] 

#include <string>
#include <vector>
#include <algorithm> //pair, count, sort
using namespace std;

bool compare(const pair<double, int> &a, const pair<double, int> &b){
	if (a.first > b.first)
    	return true; // >내림차순
	else if (a.first == b.first)
    	return a.second < b.second; // <오름차순
	else
    	return false;
}

vector<int> solution(int N, vector<int> stages) {
	vector<int> answer(0);
	int cnt[501] = { 0 };
	vector<pair<double, int>> rate; //(실패율,스테이지번호) 벡터로

	for (int i = 1; i <= N + 1; i++){ //stages 카운트한거 - cnt[i]에 저장
		cnt[i] = count(stages.begin(), stages.end(), i);
	} 

	double down = stages.size();
	for (int i = 1; i <= N; i++){ //(실패율,스테이지번호) 저장
		if (down != 0){
			rate.push_back(make_pair(cnt[i] / down, i));
			down -= cnt[i];
		}
		else
        	rate.push_back(make_pair(0, i)); //분모 0인경우 실패율0으로 처리
	} 

	sort(rate.begin(), rate.end(), compare); //실패율 기준으로 내림차순 정렬

	for (int i = 0; i < rate.size(); i++){
		answer.push_back(rate[i].second);
	}

	return answer;
}

 

 

[JAVA]

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

class Solution {
    static class Rate implements Comparable<Rate> {
        int index; double rate;
        public Rate(int index, double rate){
            this.index=index; this.rate=rate;
        }

        @Override
        public int compareTo(Rate r){
            if(this.rate>r.rate) //실패율 내림차순
                return -1;
            else if(this.rate==r.rate)
                if(this.index>r.index) //인덱스 오름차순
                    return 1;
            return 1;
        }
    }
    
    public int[] solution(int N, int[] stages) {int[] count = new int[N+2];
        for(int i=0; i<stages.length; i++){ 
            count[stages[i]]++;
        }

        List<Rate> rate = new ArrayList<>(); //(인덱스,실패율) 저장할 리스트

        double total = stages.length;
        for(int i=1; i<N+1; i++){
            if(total>0){
                rate.add(new Rate(i,(double)count[i]/total));
                total-=count[i];
            }
            else //분모=0 되면 실패율=0으로 저장
                rate.add(new Rate(i, 0));
        }

        Collections.sort(rate); //정렬
                                                
        int[] answer = new int[rate.size()];
        for(int i=0; i<rate.size(); i++){
            answer[i] = rate.get(i).index;
        }                                        
        return answer;
    }
}