[백준] 27951 옷걸이 - Greedy / Java

• 문제 링크

27951번: 옷걸이

 

• 풀이 코드

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        StringBuilder sb = new StringBuilder();

        int n = read();
        int[] arr = new int[n], cnt = new int[4];
        for (int i = 0; i < n; i++) cnt[arr[i] = read()]++;

        int u = read() - cnt[1], d = read() - cnt[2];
        for (int i = 0; i < n; i++) {
            if (arr[i] == 1) sb.append("U");
            else if (arr[i] == 2) sb.append("D");
            else {
                if (u > 0) {
                    u--;
                    sb.append("U");
                } else if (d > 0) {
                    d--;
                    sb.append("D");
                }
            }
        }

        bw.write(u == 0 && d == 0 ? "YES\n" + sb : "NO");
        bw.flush();
    }

    private static int read() throws IOException {
        int c, n = System.in.read() & 15;
        while ((c = System.in.read()) > 32) n = (n << 3) + (n << 1) + (c & 15);

        return n;
    }

}