프로그래머스 - 코딩테스트 입문 Day 3

1. 나머지 구하기

---

	class Solution {
	    public int solution(int num1, int num2) {
	        return num1 % num2;
	    }
	}

 

 

 

2. 중앙값 구하기

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	import java.util.*;

	class Solution {
	    public int solution(int[] array) {
	        Arrays.sort(array);
	        int idx = array.length / 2;
	        return array[idx];
	    }
	}

 

 

 

3. 최빈값 구하기

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import java.util.*;

class Solution {
    public int solution(int[] array) {
        int maxCount = 0;
        int answer = 0;
        Map<Integer, Integer> map = new HashMap<>();
        for(int number : array){
            int count = map.getOrDefault(number, 0) + 1;
            if(count > maxCount){
                maxCount = count;
                answer = number;
            }
            else  if(count == maxCount){
                answer = -1;
            }
            map.put(number, count);
        }
        return answer;
    }
}

 

 

 

4. 짝수는 싫어요

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class Solution {
    
    static int[] arr;
    
    public int[] solution(int n) {
        if(n%2 == 0){
            arr = new int[n/2];
        }else{
            arr = new int[n/2 + 1];
        }
        createArr(arr,n);
        return arr;
    }
    
    public static void createArr(int[] arr, int n){
        int idx = 0;
        for(int i = 1; i<=n; i++){
            if(i % 2 == 1){
                arr[idx++] = i;
            }
        }
    }
}