Exercise03_01 

 1 import javax.swing.JOptionPane;
 2 public class TheDirection {
 3     public static void main(String[] args){
 4         double a,b,c,t,r1,r2;
 5         String number;
 6         int messageType=JOptionPane.INFORMATION_MESSAGE;
 7         number=JOptionPane.showInputDialog(null,"输入a"); 
 8         a=Double.parseDouble(number);
 9         number=JOptionPane.showInputDialog(null,"输入b"); 
10         b=Double.parseDouble(number);
11         number=JOptionPane.showInputDialog(null,"输入c"); 
12         c=Double.parseDouble(number);
13         t = b*b-4*a*c;
14         if(t>0){
15             r1 = (-b+Math.pow(t,0.5))/(2*a);
16             r2 = (-b-Math.pow(t,0.5))/(2*a);
17             String message="The equation has two roots " + r1 + " and "+ r2;
18             JOptionPane.showMessageDialog(null,message,"result",messageType);
19         }
20         else if(t==0){
21             r1 = (-b+Math.pow(t,0.5))/(2*a);
22             String message="The equation has one roots " + r1;
23             JOptionPane.showMessageDialog(null,message,"result",messageType);
24         }
25         else{
26             String message="The equation has no real roots ";
27             JOptionPane.showMessageDialog(null,message,"result",messageType);
28         }
29         
30     }
31 }

 

posted @ 2018-10-16 21:17  CHERRYL  阅读(174)  评论(0)    收藏  举报