import javax.swing.JOptionPane;
public class sanjiaoxing{
public static void main(String[] s)
{ int a=0,b=0,c=0;
String bian1=JOptionPane.showInputDialog(null,"Enter a number","输入其中一条边",JOptionPane.INFORMATION_MESSAGE);
a=Integer.parseInt(bian1);
String bian2=JOptionPane.showInputDialog(null,"Enter a number","输入其中一条边",JOptionPane.INFORMATION_MESSAGE);
b=Integer.parseInt(bian2);
String bian3=JOptionPane.showInputDialog(null,"Enter a number","输入其中一条边",JOptionPane.INFORMATION_MESSAGE);
c=Integer.parseInt(bian3);
boolean roemin=(a+b>c||a+c>b||b+c>a);
JOptionPane.showMessageDialog(null,"Can edges"+" "+a+","+b+" "+"and" +" "+c+" "+"from a triagle?"+" "+roemin,"判断是不是三角 形",JOptionPane.INFORMATION_MESSAGE);
JOptionPane.showMessageDialog(null,1/2*(Math.sqrt((1/2*(a+b+c))*((1/2*(a+b+c))-a)*((1/2*(a+b+c))-b)*((1/2*(a+b+c))-c))),"该三角形的面积是:",JOptionPane.INFORMATION_MESSAGE);
}
}
我想计算面积但是计算不出来啊.
public class sanjiaoxing{
public static void main(String[] s)
{ int a=0,b=0,c=0;
String bian1=JOptionPane.showInputDialog(null,"Enter a number","输入其中一条边",JOptionPane.INFORMATION_MESSAGE);
a=Integer.parseInt(bian1);
String bian2=JOptionPane.showInputDialog(null,"Enter a number","输入其中一条边",JOptionPane.INFORMATION_MESSAGE);
b=Integer.parseInt(bian2);
String bian3=JOptionPane.showInputDialog(null,"Enter a number","输入其中一条边",JOptionPane.INFORMATION_MESSAGE);
c=Integer.parseInt(bian3);
boolean roemin=(a+b>c||a+c>b||b+c>a);
JOptionPane.showMessageDialog(null,"Can edges"+" "+a+","+b+" "+"and" +" "+c+" "+"from a triagle?"+" "+roemin,"判断是不是三角 形",JOptionPane.INFORMATION_MESSAGE);
JOptionPane.showMessageDialog(null,1/2*(Math.sqrt((1/2*(a+b+c))*((1/2*(a+b+c))-a)*((1/2*(a+b+c))-b)*((1/2*(a+b+c))-c))),"该三角形的面积是:",JOptionPane.INFORMATION_MESSAGE);
}
}
我想计算面积但是计算不出来啊.
Math.sqrt(p * ((p - a) * (p - b) * (p - c)));
不用再除2了
且运算期间不要用1/2这种形式 换用0.5
JOptionPane.showMessageDialog(null,1/2*(Math.sqrt((1/2*(a+b+c))*((1/2*(a+b+c))-a)*((1/2*(a+b+c))-b)*((1/2*(a+b+c))-c)))
楼上已经说明了
boolean roemin=(a+b>c&&a+c>b&&b+c>a);
if(roemin==true)