第三章编程练习题3.1

package exercise3;

import java.util.Scanner;

public class Main1 {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        double a = input.nextDouble();
        double b = input.nextDouble();
        double c = input.nextDouble();
        double panbieshi = b*b-4*a*c;
        if(panbieshi < 0)
        {
            System.out.println("没有值");
        }
        else if(panbieshi == 0)
        {
            double r1 = -b/(2*a);
            System.out.println(r1);
        }else{
             double r1 = (-b + Math.pow(panbieshi, 0.5)) / (2 * a);
               double r2 = (-b - Math.pow(panbieshi, 0.5)) / (2 * a);
               System.out.println("The roots are " + r1 + " and " + r2);
        }
    }

}