编辑代码

#include<iostream>
#include<cmath>                  
using namespace std;
int main()
{   
    double triangle(double,double,double);//函数声明
    double a,b,c;
    cin>>a>>b>>c;                                  //输入3个边
    while(a>0 && b>0 && c>0)
    {
        cout<<triangle(a,b,c)<<endl;                 //输出三角形的面积
        cin>>a>>b>>c;                                //输入3个边
    }
    return 0;
}

double triangle(double a,double b,double c)
{
    double area;
    double s=(a+b+c)/2;
    area=sqrt(s*(s-a)*(s-b)*(s-c));
    return area;
}