백준 18310

StringBuilder를 이용한 케이스

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer stk;
		StringBuilder sb = new StringBuilder();

		int n = Integer.parseInt(br.readLine());
		int[] num = new int[n];
		stk = new StringTokenizer(br.readLine());
		for (int i = 0; i < n; i++)
			num[i] = Integer.parseInt(stk.nextToken());
		
		Arrays.sort(num);

		sb.append(num[(n - 1) / 2]);
		System.out.println(sb);
	}
}

일반적인 방법 (배열 대신 리스트 가능)

import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int N = Integer.parseInt(br.readLine());
        int[] arr = new int[N];
        
        StringTokenizer st = new StringTokenizer(br.readLine());
        for (int i = 0; i < N; i++) arr[i] = Integer.parseInt(st.nextToken());
        
        Arrays.sort(arr);
        
        if (N % 2 == 0) System.out.println(arr[(N / 2) - 1]);
        else System.out.println(arr[(N - 1) / 2]);
    }
}