[백준 Java] 심화 1 - 25206번: 너의 평점은

 

 

import java.io.*;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        Map<String, Double> gradeMap = new HashMap<>();
        gradeMap.put("A+", 4.5);
        gradeMap.put("A0", 4.0);
        gradeMap.put("B+", 3.5);
        gradeMap.put("B0", 3.0);
        gradeMap.put("C+", 2.5);
        gradeMap.put("C0", 2.0);
        gradeMap.put("D+", 1.5);
        gradeMap.put("D0", 1.0);
        gradeMap.put("F", 0.0);

        double totalCredit = 0; // 학점만
        double totalScore = 0; // 총합

        for (int i = 0; i < 20; i++) {
            StringTokenizer st = new StringTokenizer(br.readLine());
            st.nextToken(); // 첫 번째 토큰 (과목명) 무시
            double credit = Double.parseDouble(st.nextToken());
            String grade = st.nextToken();

            if (!grade.equals("P")) { // "P" 과목 외만 계산
                totalCredit += credit;
                totalScore += credit * gradeMap.get(grade);
            }
        }

        bw.write(String.valueOf((totalCredit == 0) ? 0.0 : totalScore / totalCredit));

        br.close();
        bw.flush();
        bw.close();
    }
}