情報科学I

Area.java

public class Area
{
    public static void main(String args[]) {
        double width  = Integer.parseInt(args[0]);
        double height = Integer.parseInt(args[1]);
        System.out.println("Input Width   : " + width);
        System.out.println("Input Height  : " + height);
        System.out.println("Triangle Area : " + width * height / 2.0);
        System.out.println("Square Area   : " + width * height);        
        System.out.println("Circle Area   : " + width * width * 3.14);
    }
}

SalesTax.java

public class SalesTax
{
    public static void main(String args[]) {
        if(args.length != 3) {
            System.err.println("Invalid argument numbers");
            System.err.println("Please input Price, Year, and Month");
            return;
        }
        int price = Integer.parseInt(args[0]);
        int year  = Integer.parseInt(args[1]);
        int month = Integer.parseInt(args[2]);
        if(year < 0) {
            System.err.println("Invalid month");
            return;
        }
        if(month < 0 || month > 12) {
            System.err.println("Invalid year");
            return;
        }
        double tax_rate;
        // if文を使う演習なので...
        if(year >= 1998 || (year == 1997 && month >= 4)) {
            // 1997年4月以降(1998年以降 + 1997年4～12月)
            tax_rate = 0.05;
        } else {
            // 1997年4月以前
            tax_rate = 0.03;
        }
        System.out.println("Input Price  : " + price);
        System.out.println("Input Year   : " + year);
        System.out.println("Input Mounth : " + month);
        System.out.println("");
        System.out.println("Sales tax    : " + price * tax_rate);
    }
}