[백준] 9498번 : 시험 성적 - Java

https://www.acmicpc.net/problem/9498

9498번: 시험 성적

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구현 방법

입력 방식

• Scanner
• BufferedReader
  readLine()으로 입력 받아 연산
  이때 String 타입으로 입력되기에 Integer.parseInt()를 통해 String ➡ int으로 형변환 필수

 

조건 필터 방식

• if 문
• if 문 + 삼항연산자

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풀이

1.1. Scanner + if 문

import java.util.Scanner;

public class Main { 
    public static void main(String[] args) {
    
        //입력
        Scanner in = new Scanner(System.in);
        int A = in.nextInt();
        in.close();
		
        //조건 필터
        if(A >= 90) System.out.println("A");
        else if(A >= 80) System.out.println("B");
        else if (A >= 70) System.out.println("C");
        else if(A >= 60) System.out.println("D");
        else System.out.println("F");
    }
}

 

1.2. Scanner + if 문 + 삼항연산자

import java.util.Scanner;

public class Main { 
    public static void main(String[] args) {

        //입력
        Scanner in = new Scanner(System.in);
        int A = in.nextInt();
        in.close();
		
        //조건 필터
        System.out.print((A >= 90) ? "A"
            : (A >= 80) ? "B"
            : (A >= 70) ? "C"
            : (A >= 60)? "D"
            : "F");
    }
}

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2.1. BufferedReader + if 문

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
 
public class Main {
    public static void main(String[] args) throws IOException {
        
        //입력
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int A = Integer.parseInt(br.readLine()); //String to int
        
        //조건 필터
        if(A >= 90) System.out.println("A");
        else if(A >= 80) System.out.println("B");
        else if (A >= 70) System.out.println("C");
        else if(A >= 60) System.out.println("D");
        else System.out.println("F");
    }
}

 

2.2. BufferedReader + if 문 + 삼항연산자

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;

public class Main {
    public static void main(String[] args) throws Exception {
	
        //입력
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int A = Integer.parseInt(br.readLine()); //String to int
        
        //조건 필터
        System.out.print((A >= 90) ? "A"
            : (A >= 80) ? "B"
            : (A >= 70) ? "C"
            : (A >= 60) ? "D"
            : "F");
    }
}

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성능

•  BufferedReader > Scanner

 

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출처 : https://st-lab.tistory.com/22