국내주식 / 일본주식 / 개발자이야기

import java.util.*;

class Solution {
    public int solution(int[] nums) {
        int answer = 0;
        int pick = nums.length / 2;
        
        HashSet<Integer> set = new HashSet<>(); // 중복저장이 안되는 해시셋
        
        for(int n : nums)
        {
            set.add(n); // 헤시셋에 추가한다.
        }
        
        if(pick >= set.size())
            answer = set.size(); //폰켓몬 종류보다 고를 수 있는 수가 많으면 그냥 그대로 폰켓몬 수를 대입한다.
        else
            answer = pick; // 그렇지 않으면 픽할 수 있는 수를 대입한다.
        return answer;
    }   
}

// 자바는 처음이라 솔직히 다른 사람 거를 봤다.

public class Solution {

    public int solution(int[][] param) {
        int safeZone = 0;
        // 위험지역 Set
        for (int i = 0; i < param.length; i++) 
        {
            for (int j = 0; j < param.length; j++) 
            {
                if (param[i][j] == 1)
                    setArea(param, i, j);
            }
        }
        // 안전지역 Count
        
        for (int i = 0; i < param.length; i++) 
        {
            for (int j = 0; j < param.length; j++) 
            {
                if (param[i][j] == 0)
                    safeZone++;
            }
        }

        return safeZone;
    }

    void setArea(int[][] param, int x, int y) {
        for (int i = -1; i < 2; i++) 
        {
            for (int j = -1; j < 2; j++) 
            {
                try 
                {
                    if (param[x + i][y + j] == 0)
                        param[x + i][y + j] = 2;
                } 
                catch (Exception e) 
                {
                }
            }
        }
    }

}

public class Solution {
    int[][] d = {{-1, -1}, {-1, 0}, {-1, 1}, {0, -1}, {0, 0}, {0, 1}, {1, -1}, {1, 0}, {1, 1}};

    public int solution(int[][] board) {
        int n = board.length;
        boolean[][] unable = new boolean[n][n];
        
        for (int i = 0; i < n; i++) 
        {
            for (int j = 0; j < n; j++) 
            {
                if (board[i][j] == 1) 
                {
                    for (int[] k: d) 
                    {
                        int nearX = i + k[0];
                        int nearY = j + k[1];
                        
                        if (nearX >= 0 && nearX < n && nearY >= 0 && nearY < n) 
                        {
                            unable[nearX][nearY] = true;
                        }
                    }
                } 
            }
        }

        int unableCount = 0;
        
        for (int i = 0; i < n; i++) 
        {
            for (int j = 0; j < n; j++) 
            {
                if (unable[i][j]) 
                {
                    unableCount++;
                }
            }
        }
        
        return n * n - unableCount;
    }
}

////////////////////////

public class Solution {
    public int solution(int[,] board) {
        int answer = 0;
        int length = board.GetLength(0);
        int[] x = new int[8]{-1, 1, 0, 0, -1, -1, 1, 1};
        int[] y = new int[8]{0, 0, -1, 1, -1, 1, -1, 1};
        int[,] temp = new int[length,length]; 
        int nx = 0;
        int ny = 0;
        
        for(int i = 0; i < length; i++)
        {
            for(int j = 0; j < length; j++)
            {
                if(board[i,j] == 1)
                {
                    temp[i,j] = 1;
                    for(int k = 0; k < 8; k++)
                    {
                        nx = i + x[k];
                        ny = j + y[k];
                        if(nx >= 0 && nx < length && ny >= 0 && ny < length)
                        {
                            temp[nx,ny] = 1;
                        }
                    }
                }
            }
        }
        
        for(int i = 0; i < length; i++)
        {
            for(int j = 0; j < length; j++)
            {
                if(temp[i,j] != 1)
                {
                    answer++;
                }
            }
        }   
        return answer;
    }
}

////////////////////////

C#

using System;

public class Solution {
    public int solution(int[,] board) {
        int safeZone = 0;
        // 위험지역 Set
        for (int i = 0; i < board.GetLength(0); i++) 
        {
            for (int j = 0; j < board.GetLength(1); j++) 
            {
                if (board[i,j] == 1)
                    setArea(board, i, j);
            }
        }
        // 안전지역 Count
        
        for (int i = 0; i < board.GetLength(0); i++) 
        {
            for (int j = 0; j < board.GetLength(1); j++) 
            {
                if (board[i,j] == 0)
                    safeZone++;
            }
        }

        return safeZone;
    }

    void setArea(int[,] board, int x, int y) {
        for (int i = -1; i < 2; i++) 
        {
            for (int j = -1; j < 2; j++) 
            {
                try 
                {
                    if (board[x + i,y + j] == 0)
                        board[x + i,y + j] = 2;
                } 
                catch (Exception e) 
                {
                }
            }
        }
    
    }
}

//// try catch(Exception e)를 활용해서 어레이의 범위를 벗어나는 경우를 빠져나오게 하는 방식이다.

/// 그리고 폭탄의 영향 범위 지역을 2로 세팅해서 safezone의 숫자를 계산할 수 있도록 설정했다.

class Solution {
    public String solution(String polynomial) { 
        String answer = "";
        int x_num = 0;
        int constant = 0;
        String[] words = polynomial.split("\\+");
        
        for( int i = 0 ; i < words.length ; i++ )
        {
            String word = words[i].trim();
            System.out.println( word );
            
            if( word.endsWith("x") )
            {
                if( word.length() == 1 ) x_num += 1;
                else x_num += Integer.parseInt( word.substring( 0, word.length() - 1 ) );
            }                                 
            else 
              constant += Integer.parseInt( word );
        }

        if ( x_num == 0 ) 
          answer = String.valueOf( constant );
        else if( constant == 0 ) 
        {
            if( x_num == 1 ) answer = "x";
            else answer = x_num + "x";
        }
        else if ( constant == 0 && x_num == 0 ) 
          answer = "0";
        else 
        {
            if( x_num == 1 ) answer = "x + " + constant;
            else answer =  x_num + "x + " + constant;
        }

        return answer;
    }
}

C#

using System;

public class Solution {
    public string solution(string polynomial) {
        string answer = "";
        string temp = "";
        string[] str = polynomial.Split(" ");
        int xNum = 0;
        int num = 0;
        
        for(int i = 0; i < str.Length; i+=2)
        {
            // Contains()을 활용해 str[i]에 x가 있는지 확인
            if(str[i].Contains("x"))
            {
                // temp에 str[i].Replace를 활용해 x를 string.Empty로 초기화
                temp = str[i].Replace("x", string.Empty);
                // temp에 값이 없으면 xNum에 1을 더함
                if(temp == "")
                {
                    xNum += 1;
                }
                // temp에 값이 있으면 xNum에 int형으로 변환후 더함
                else
                {
                    xNum += int.Parse(temp);
                }
            }
            else
            {
                num += int.Parse(str[i]);
            }
        }
        if(num == 0)
        {
            if(xNum == 1)
            {
                answer = "x";
            }
            else
            {
                answer = xNum.ToString() + "x";
            }
        }
        else
        {
            if(xNum == 0)
            {
                answer = num.ToString();
            }
            else if(xNum == 1)
            {
                answer = "x " + "+ " + num.ToString();
            }
            else
            {
                answer = xNum.ToString() + "x " + "+ " + num.ToString();
            }
        }
        return answer;
    }
}

using System;
using System.Collections.Generic;
using System.Linq;

public class Solution {
    public int[] solution(int[] fees, string[] records) {
        
        List<string> newRecords = new List<string>();
        Dictionary<string, List<string>> dicList = new Dictionary<string, List<string>>();
        List<int> answerList = new List<int>();

        for (var i=0; i< records.Length; i++)
        {
            var tmp = records[i].Split(' ');
            var list = records.Where(w => w.Substring(6, 4) == tmp[1]).OrderBy(o => o);

            if(!dicList.ContainsKey(tmp[1]))
            {
                dicList.Add(tmp[1], list.ToList());
            }
        }

        var result = dicList.OrderBy(o => o.Key);
        double totalMinute = 0;
        
        foreach(var dic in result)
        {
            DateTime inTime = DateTime.Now;
            DateTime outTime = DateTime.Now;

            for (var i=0;i< dic.Value.Count;i++ )
            {
                var time = dic.Value[i].Split(' ')[0];
                var gb = dic.Value[i].Split(' ')[2];

                if (gb == "IN")
                {
                    inTime = Convert.ToDateTime(DateTime.Now.ToString("yyyy-MM-dd") + " " + time);
                }
                else
                {
                    outTime = Convert.ToDateTime(DateTime.Now.ToString("yyyy-MM-dd") + " " + time);

                    TimeSpan dateDiff = outTime - inTime;
                    totalMinute += Convert.ToInt32(dateDiff.TotalMinutes);
                }
            }

            // 출차기록이 없으면 23:59 분 출차로 기록
            if (dic.Value.Count % 2 != 0)
            {
                outTime = Convert.ToDateTime(DateTime.Now.ToString("yyyy-MM-dd") + " 23:59");

                TimeSpan dateDiff2 = outTime - inTime;
                totalMinute += Convert.ToInt32(dateDiff2.TotalMinutes);
            }

            double parkingPrice = 0;

            if (totalMinute <= fees[0])
            {
                parkingPrice = fees[1];
            }
            else
            {
                parkingPrice = fees[1] + Math.Ceiling((totalMinute - fees[0]) / fees[2]) * fees[3];
            }

            answerList.Add(Convert.ToInt32(parkingPrice));
            totalMinute = 0;
        }

        var answer = answerList.ToArray();

        return answer;
    }
}

//////////////////

using System;
using System.Collections.Generic;
using System.Linq;

public class Solution {
    public int[] solution(int[] fees, string[] records) {
        List<string> cars = new List<string>();
        Dictionary<string, int> recDic = new Dictionary<string, int>();
        Dictionary<string, int> tempDic = new Dictionary<string, int>();

        for(int i = 0; i < records.Length; i++)
        {
            string[] rec = records[i].Split(' ');
            if(rec[2] == "IN")
            {
                int inTime = int.Parse(rec[0].Substring(0, 2)) * 60 + int.Parse(rec[0].Substring(3, 2));

                if(!recDic.ContainsKey(rec[1]))
                {
                    cars.Add(rec[1]);
                    tempDic.Add(rec[1], inTime);
                }
                else
                    tempDic[rec[1]] = inTime;
            }
            else
            {
                int outTime = int.Parse(rec[0].Substring(0, 2)) * 60 + int.Parse(rec[0].Substring(3, 2));

                if(!recDic.ContainsKey(rec[1]))
                    recDic.Add(rec[1], outTime - tempDic[rec[1]]);
                else
                    recDic[rec[1]] += outTime - tempDic[rec[1]];

                tempDic[rec[1]] = -1;
            }
        }
        
        cars.Sort();
        int[] answer = new int[cars.Count];
        
        for(int i = 0; i < cars.Count; i++)
        {
            int time = 0;
            if(!recDic.TryGetValue(cars[i], out time) || tempDic[cars[i]] != -1)
                time += 1439 - tempDic[cars[i]];

            answer[i] = fees[1];
            if(time > fees[0])
            {
                time -= fees[0];
                answer[i] += (time / fees[2]) * fees[3];
                if(time % fees[2] != 0)
                    answer[i] += fees[3];
            }
        }
        return answer;
    }
}

using System;
using System.Linq;

public class Solution {
    public string solution(int[] food) {
        string answer = "";
        int times = 0;
        
        for(int i = 1; i<food.Length;i++)
        {
            times = food[i]/2;
            
            for(int j = 0;j<times;j++)
            {
                answer += i;    
            }
        }
        
        answer += 0;
        
        for(int i = food.Length-1; i>0;i--)
        {
            times = food[i]/2;
            
            for(int j = 0;j<times;j++)
            {
                answer += i;    
            }
        }
        
        return answer;
    }
}

////////////////

using System;
using System.Linq;

public class Solution {
    public string solution(int[] food) {
        string answer = "0";
        int times = 0;
        
        for (int i = food.Length - 1; i > 0; i--) 
        {
            for (int j = 0; j < food[i] / 2; j++) 
            {
                answer = i + answer + i; 
            }
        }

        return answer;
    }
}

using System;
using System.Collections.Generic;
public class Solution
{
    public string solution(int[] food)
    {
        string answer = "";
        for(int i = 1; i < food.Length; i++)
        {
            int nowCount = food[i] / 2;
            for(int count = 0; count < nowCount; count++)
            {
                answer += i.ToString();
            }
        }
        char[] temp = answer.ToCharArray();
        Array.Reverse(temp);
        string back = new string(temp);
        answer += "0" + back;
        return answer;
    }
}

파이썬

/////

def solution(food):
    answer ="0"
    for i in range(len(food)-1, 0,-1):
        c = int(food[i]/2)
        while c>0:
            answer = str(i) + answer + str(i)
            c -= 1
    return answer

////

def solution(food):
    answer = ''
    rev=''
    for i in range(1,len(food)):
        answer+=str(i)*(food[i]//2)
    rev=answer[::-1]
    answer+='0'

    return answer+rev

자바

/////

class Solution {
    public String solution(int[] food) {
        String answer = "0";

        for (int i = food.length - 1; i > 0; i--) 
        {
            for (int j = 0; j < food[i] / 2; j++) 
            {
                answer = i + answer + i; 
            }
        }

        return answer;
    }
}

using System;
using System.Collections;
using System.Collections.Generic;

public class Solution 
{
    public int[] solution(string[] id_list, string[] report, int k) 
    {
        int[] answer = new int[id_list.Length];

        Dictionary<string, List<string>> dic = new Dictionary<string, List<string>>();

        for (int i = 0; i < report.Length; i++)
        {
            string[] str = report[i].Split(' ');

            string give = str[0];
            string take = str[1];

            if (!dic.ContainsKey(take))
            {
                List<string> list = new List<string>();
                list.Add(give);
                dic.Add(take, list);
                continue;
            }

            if (!dic[take].Contains(give))
            {
                dic[take].Add(give);
            }
        }

        for (int i = 0; i < id_list.Length; i++)
        {
            foreach (KeyValuePair<string, List<string>> item in dic)
            {
                if (item.Value.Contains(id_list[i]))
                {
                    if (item.Value.Count >= k)
                    {
                        answer[i] = ++answer[i];
                    }
                }                
            }
        }

        return answer;
    }
}

//딕셔너리의 활용이 중요하다.

using System;
using System.Linq;

public class Solution {
    public int[] solution(string[] id_list, string[] report, int k) {
        int[] answer = new int[id_list.Length]; // 결과 배열.

        int[] receive = new int[id_list.Length]; // 신고받은 횟수.
        int[] send = new int[id_list.Length];    // 신고한 횟수.

        report = report.Distinct().ToArray();
        // 중복 삭제하기

        // 신고받은 횟수를 기록.
        for (int i = 0; i < report.Length; i++) 
        {
            string report_str = report[i].Split(' ')[1];
            int report_index = Array.IndexOf(id_list, report_str);
            // 신고받은 인덱스 횟수
            receive[report_index]++;
        }

        // 신고받은 횟수가 k보다 높을 시 answer 값을 상승.
        for (int i = 0; i < report.Length; i++) 
        {
            string report_str = report[i].Split(' ')[1];
            int report_index = Array.IndexOf(id_list, report_str);

            if (receive[report_index] >= k) 
            {
                string send_str = report[i].Split(' ')[0];
                int send_index = Array.IndexOf(id_list, send_str);
                answer[send_index]++;
            }
        }

        return answer;
    }
}

using System;
using System.Linq;
using System.Collections.Generic;

public class Solution {
    public int[] solution(string[] id_list, string[] report, int k) {
             var tReport = report.Distinct().
                Select(s => s.Split(' ')).
                GroupBy(g => g[1]).
                Where(w => w.Count() >= k).
                SelectMany(sm => sm.Select(s => s[0])).
                ToList();

            return id_list.ToDictionary(x => x, x => tReport.Count(c => x == c)).Values.ToArray();
    }
}

파이썬

//////

def solution(id_list, report, k):
    answer = [0] * len(id_list)    
    reports = {x : 0 for x in id_list}

    for r in set(report):
        reports[r.split()[1]] += 1

    for r in set(report):
        if reports[r.split()[1]] >= k:
            answer[id_list.index(r.split()[0])] += 1

    return answer

def solution(id_list, report, k):
    answer = [0] * len(id_list)
    dic_report = {id: [] for id in id_list} # 해당 유저를 신고한 ID
    for i in set(report):
        i = i.split()
        dic_report[i[1]].append(i[0])

    for key, value in dic_report.items():
        if len(value) >= k:
            for j in value:
                answer[id_list.index(j)] += 1

    return answer

자바

//////

import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.stream.Collectors;

class Solution {
    public int[] solution(String[] id_list, String[] report, int k) {
        List<String> list = Arrays.stream(report).distinct().collect(Collectors.toList());
        HashMap<String, Integer> count = new HashMap<>();
        
        for (String s : list) 
        {
            String target = s.split(" ")[1];
            count.put(target, count.getOrDefault(target, 0) + 1);
        }

        return Arrays.stream(id_list).map(_user -> {
            final String user = _user;
            List<String> reportList = list.stream().filter(s -> s.startsWith(user + " ")).collect(Collectors.toList());
            return reportList.stream().filter(s -> count.getOrDefault(s.split(" ")[1], 0) >= k).count();
        }).mapToInt(Long::intValue).toArray();
    }
}

///////

import java.util.*;
class Solution {
 public int[] solution(String[] id_list, String[] report, int k) {
        // key: 신고당한놈, value: 몇명한테 당했는지
        Map<String, Set<String>> map = new HashMap<>();

        for (String rep : report) 
        {
            String[] arr = rep.split(" ");
            Set<String> set = map.getOrDefault(arr[1], new HashSet<>());
            set.add(arr[0]);
            map.put(arr[1], set);
        }

        // key: 알림받을 놈, value: 몇번 알림받을지
        Map<String, Integer> countMap = new LinkedHashMap<>();

        for (String id : id_list) 
        {
            countMap.put(id, 0);
        }

        for (Map.Entry<String, Set<String>> entry : map.entrySet()) 
        {
            if (entry.getValue().size() >= k) 
            { // 정지당할놈
                for (String value : entry.getValue()) 
                {
                    countMap.put(value, countMap.getOrDefault(value, 0) + 1);
                }
            }
        }

        return countMap.values().stream().mapToInt(Integer::intValue).toArray();
    }
}

using System;

public class Solution {
    public int solution(int a, int b, int n) {
        int answer = 0;
        int index = n;
        
        while(n > n%a)
        {
            answer += (n/a)*b;
            n = n%a+(n/a)*b;
        }
        
        return answer;
    }
}

/////

public class Solution {
    public int solution(int a, int b, int n) {
        return (n > b ? n - b : 0) / (a - b) * b;
    }
}

파이썬

//////

def solution(a, b, n):
    answer = 0
    while n >= a:
        answer += (n // a) * b
        n = (n // a) * b + (n % a)
    return answer

자바

class Solution {
    public int solution(int a, int b, int n) {
        int answer = 0;

        while (n >= a) 
        {
            answer += b * (n / a);
            n = b * (n / a) + n % a;
        }

        return answer;
    }
}

using System;

public class Solution {
    public int solution(int[] numbers) {
        int sum = 0;
        
        for(int i = 0;i<numbers.Length;i++)
        {
            sum += numbers[i];
        }
        
        return 45-sum;
    }
}

//////

using System;
using System.Collections.Generic;
using System.Linq;


public class Solution {
    public int solution(int[] numbers) {
        var numberArray = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            return numberArray.Except(numbers).Sum();
    }
}

파이썬

def solution(numbers):
    return 45 - sum(numbers)

자바

class Solution {
    public int solution(int[] numbers) {
        int sum = 45;
        for (int i : numbers) {
            sum -= i;
        }
        return sum;
    }
}