Quiz

🔓 전기 요금 계산하기

전기요금1 = 기본요금 + (사용량 kw당요금)
전기요금2(최종요금) = 전기요금 + 전기요금세율

🔑 if / else if

package pack_CtrlQuiz;

import java.util.Scanner;

public class Charge {

	public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		
		System.out.print("코드번호를 입력하세요"
      			 + "(1 - 가정용, 2 - 산업용, 3 - 교육용) : ");
		int code = scanner.nextInt();
		System.out.print("전기 사용량을 입력하세요(kw) : ");
		int used = scanner.nextInt();
		
		scanner.close();
		
		double basic = 0;;
		double perKw = 0;;
		double taxRate = 0;
		double charge = 0;
		
		if (code == 1) {
			basic = 1130;
			perKw = 127.8;
			taxRate = 0.09;
		} else if (code == 2){
			basic = 660;
			perKw = 88.5;
			taxRate = 0.08;
		} else if (code == 3) {
			basic = 370;
			perKw = 52.;
			taxRate = 0.05;
		}
		
		charge = basic + (used*perKw);
		double chargeAfterTax = charge + (charge*taxRate);
        
		System.out.printf("전기요금은 %.0f원입니다.", chargeAfterTax);
	}

}

🔑 switch

package pack_CtrlQuiz;

import java.util.Scanner;

public class Charge2 {

	public static void main(String[] args) {
		
		int code;
		int used;
		double basic = 0;
		double perKw = 0;
		double charge = 0;
		double taxRate = 0;
		
		Scanner scanner = new Scanner(System.in);
		System.out.print("코드번호를 입력하세요"
      				  + "(1 - 가정용, 2 - 산업용, 3 - 교육용) : ");
		code = scanner.nextInt();
		System.out.print("전기 사용량을 입력하세요(kw) : ");
		used = scanner.nextInt();
		scanner.close();
		
		switch (code) {
		case 1:
			 basic = 1130;
			 perKw = 127.8;
			 taxRate = 0.09;
			break;
		case 2:
			 basic = 660;
			 perKw = 88.5;
			 taxRate = 0.08;
			break;
		case 3:
			 basic = 370;
			 perKw = 52.;
			 taxRate = 0.05;
			break;
		}
		
		charge = basic + (used * perKw);
		double finalCharge = charge + (charge*taxRate);
        
		System.out.printf("전기요금은 %.0f원입니다.", finalCharge);
		
	}

}

🔓 원주율 계산하기

package pack_Circle;

import java.util.Scanner;

public class Area {

	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);

		System.out.print("반지름을 입력하세요 : ");
		int radius = scanner.nextInt();
	
		scanner.close();
		
		double area =  3.14 * (Math.pow(radius,2));
		
		System.out.printf("면적 : %.2f", area);
		
	}

}

거듭제곱 => Math.pow(double밑수, double지수);

🔓 메뉴에 따른 사칙연산

package pack_CalcSystem;

import java.util.Scanner;

public class Arithmetic {

	public static void main(String[] args) {

		System.out.println("====<메뉴>====\n1. 덧셈(add)\n2. 뺄셈(sub)"
			+ "\n3. 곱셈(mul)\n4. 나눗셈(div)\n============");
		
		
		Scanner scanner = new Scanner(System.in);
		
		System.out.print("\n원하는 메뉴를 선택하세요 : ");
		int code = scanner.nextInt();
		
		System.out.print("\n두 개의 숫자를 입력하세요 : ");
		double num1 = scanner.nextDouble();
		double num2 = scanner.nextDouble();
		
		scanner.close();
		
		double res = 0;
		
		if (code == 1) {
			res = num1 + num2;
		} 
		else if (code == 2) {
			res = num1 - num2;
		} 
		else if (code == 3) {
			res = num1 * num2;
		} 
		else if (code == 4) {
			res = num1 / num2;
		}

		System.out.printf("결과 값은 %.2f 입니다.", res);
	}
}

🔓 가장 작은 값 찾기

package pack_Array;

import java.util.Scanner;

public class BigNum {

	public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		
		System.out.print("임의의 숫자 다섯 개를 입력하세요 : ");
		double[] num = new double[5];
		
		for (int i = 0; i < num.length; i++) {
			num[i] = scanner.nextDouble();
		}
		
		scanner.close();
		
		double min = num[0];
		
		for (int i = 0; i < num.length; i++) {
			
			if (num[i] < min) {
				num[i] = min;
			}
		}
		
		System.out.printf("가장 작은 값 : %.1f", min);
	}

}

🔓 급여 출력하기

package pack_Pay;

import java.util.Scanner;

public class Salary {

	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);
		System.out.print("급여를 입력해 주세요(단위. 원) : ");
		int money = scanner.nextInt();
		scanner.close();
		
		double salary = money - (money * 0.033);
		
		System.out.printf("실지급액 : %.0f 원", salary);
	}

}

🔓 inch - cm 변환하기

package pack_Conversion;

import java.util.Scanner;

public class Inch {

	public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		System.out.print("센티미터 길이 입력 : ");
		int cm = scanner.nextInt();
		scanner.close();
		
		double inch = cm / 2.54;
		
		System.out.printf("%d cm %.1f inch", cm, inch);
	}

}

🔓 누적 구하기

package pack_Sum;

import java.util.Scanner;

public class Sum {

	public static void main(String[] args) {
		
		Scanner scanner = new Scanner(System.in);
		
		System.out.print("2개의 값을 입력하세요 : ");
		int num1 = scanner.nextInt();
		int num2 = scanner.nextInt();
		
		scanner.close();
		
		int start = num1;
		int end = num2;
		int sum = 0;
		
		if (num1 > num2) {
			start = num2;
			end = num1;
			
		for (int i = start; i <= end; i++) {
			sum += i;			
			}
			
		}
		
		System.out.printf("%d부터 %d까지의 누적 합 : %d",
        					start, end, sum);
	}

}