海伦公式求三角形面积:
public class Arith {
public void arith(double a, double b,double c) {
if((a + b > c)&&(a + c > b)&&(b + c > a)&&(a - b < c)&&(
a - c < b)&&(b - c < a)) {
double z;
double p =(a + b + c);
z = Math.sqrt(p * (p - a) * (p - b) * (p - c));
System.out.print(z);
}
}
}
主程序:
import java.util.*;
public class Main {
static double a;
static double b;
static double c;
public static void main(String[] args) {
Arith brith = new Arith();
NewScanner newscanner =new NewScanner();
Scanner scan = new Scanner(System.in);
System.out.println("输入三角形三边");
if(scan.hasNextDouble()) {
a = scan.nextDouble();
}
System.out.println("第二条边");
if(scan.hasNextDouble()) {
b = scan.nextDouble();
}
System.out.println("第三条边");
if(scan.hasNextDouble()) {
a = scan.nextDouble();
}
brith.arith(a, b, c);
// TODO Auto-generated method stub
}
}