HashMap, TreeSet

상태

완료

담당자

1) 학급 회장

설명

package com.company.hashmap;

import java.util.HashMap;
import java.util.Scanner;

public class ClassPresident {
    public static void main(String [] args) {
        ClassPresident classPresident = new ClassPresident();
        Scanner in = new Scanner(System.in);
        int count = in.nextInt();
        String str = "";
        str = in.next();
        classPresident.solution(count, str);
    }

    void solution(int count, String str) {
        int max = Integer.MIN_VALUE;
        char leader = 'N';
        char [] arr = str.toCharArray();

        HashMap<Character, Integer> vote = new HashMap<>();
        for (char c : arr) {
            vote.put(c, vote.getOrDefault(c, 0)+1);
        }

        for (Character character : vote.keySet()) {
            int value = vote.get(character);
            if (max<value) {
                leader = character;
                max = value;
            }
        }
        System.out.println(leader);
    }
}
Java
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2) 아나그램

설명

public class Anagram {
    public static void main(String [] args) {
        Anagram anagram = new Anagram();
        Scanner in = new Scanner(System.in);
        String str1 = in.next();
        String str2 = in.next();
        anagram.solution(str1, str2);
    }

    void solution(String str1, String str2) {
        HashMap<Character, Integer> map = new HashMap<>();
        String result = "YES";

        char[] arr1 = str1.toCharArray();

        for (char c : arr1) {
            map.put(c, map.getOrDefault(c,0)+1);
        }

        char[] arr2 = str2.toCharArray();
        for (char c : arr2) {
            map.put(c, map.get(c)-1);
        }

        for (Character character : map.keySet()) {
            if(map.get(character) != 0) {
                result = "NO";
            }
        }
        System.out.println(result);
    }
}
Java
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3) 매출액의 종류

설명

package com.company.hashmap;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Scanner;

public class SaleType {
    public static void main(String [] args) {
        SaleType saleType = new SaleType();

        Scanner in = new Scanner(System.in);
        int count = in.nextInt();
        int k = in.nextInt();
        int [] arr = new int[count];
        for (int i=0; i<count; i++) {
            arr[i] = in.nextInt();
        }

        saleType.solution(count, k, arr);
    }

    void solution(int count, int k, int [] arr) {
        ArrayList<Integer> answer = new ArrayList<>();
        for (Integer integer : answer) {

        }
        HashMap<Integer, Integer> map = new HashMap<>();
        for (int i=0; i<k-1; i++) {
            map.put(arr[i], map.getOrDefault(arr[i],0)+1);
        }

        int lt = 0;
        for (int rt=k-1; rt<count; rt++) {
            map.put(arr[rt], map.getOrDefault(arr[rt],0)+1);
            answer.add(map.size());
            map.put(arr[lt], map.getOrDefault(arr[lt],0)-1);
            int getLtval = map.get(arr[lt]);
            if (getLtval == 0) {
                map.remove(arr[lt]);
            }
            lt++;
        }

        for (Integer integer : answer) {
            System.out.println(integer);

        }
    }
}
Java
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4) 모든 아나그램 찾기

설명

package com.company.hashmap;

import java.util.HashMap;
import java.util.Scanner;

public class SearchAllAnagram {
    public static void main(String [] args) {
        SearchAllAnagram searchAllAnagram = new SearchAllAnagram();
        Scanner in = new Scanner(System.in);
        String str1 = in.next();
        String str2 = in.next();
        searchAllAnagram.solution(str1, str2);
    }

    void solution(String str1 ,String str2) {
        int answer = 0;
        HashMap<Character, Integer> map = new HashMap<>();
        HashMap<Character, Integer> map2 = new HashMap<>();
        char [] arr1 = str1.toCharArray();
        char [] arr2 = str2.toCharArray();
        for (char c : arr2) {
            map2.put(c, map.getOrDefault(c, 0)+1);
        }

        for (int i=0; i<arr2.length-1; i++) {
            map.put(arr1[i], map.getOrDefault(arr1[i], 0)+1);
        }

        int lt = 0;
        for (int rt = arr2.length-1; rt<arr1.length; rt++) {
            map.put(arr1[rt], map.getOrDefault(arr1[rt], 0)+1);
            if (map.equals(map2)) {
                answer++;
            }
            map.put(arr1[lt], map.getOrDefault(arr1[lt], 0)-1);
            if (map.get(arr1[lt]) == 0) {
                map.remove(arr1[lt]);
            }
            lt++;
        }
        System.out.println(answer);
    }
}
Java
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5) K번째 큰수

설명

package com.company.hashmap;

import java.util.Comparator;
import java.util.Scanner;
import java.util.TreeSet;

public class LargestNumber {
    public static void main(String [] args) {
        LargestNumber largestNumber = new LargestNumber();
        Scanner in = new Scanner(System.in);
        int count = in.nextInt();
        int k = in.nextInt();
        int [] arr = new int[count];
        for (int i=0; i<count; i++) {
            arr[i] = in.nextInt();
        }

        largestNumber.solution(count, k, arr);
    }

    void solution(int count, int k, int [] arr) {
        int answer = -1;
        int numberCount = 0;
        TreeSet<Integer> tSet = new TreeSet<>(Comparator.reverseOrder());
        for (int i=0; i<count; i++) {
            for (int j=i+1; j<count; j++) {
                for (int l=j+1; l<count; l++) {
                    tSet.add(arr[i] + arr[j] + arr[l]);
                }
            }
        }
        for (Integer integer : tSet) {
            numberCount++;
            if (numberCount == k) {
                answer = integer;
            }
        }
        System.out.println(answer);
    }
}
Java
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