请高手指点，谢谢啦！
代码如下：
#include <iostream>
#include <math.h>
#include <stdio.h>

using namespace std;

int main()
{
   double a[10000],b[10000],c[10000]; //三角形三边长
   int x1[10000],y1[10000],x2[10000],y2[10000],x3[10000],y3[10000];  //三角形三点坐标
   double p,s;  //s 三角形面积

  double godistance(int x1,int y1,int x2,int y2);

   int n;
   //cin>>n;

  // cout<<"请分别输入三定点的坐标:";
   for (int i=0;i<10000;i++)
   {
     cin>>x1[i]>>y1[i]>>x2[i]>>y2[i]>>x3[i]>>y3[i];
     n++;
     if(((x1[i]==x2[i])&&(y1[i]==y2[i]))||((x1[i]==x3[i])&&(y1[i]==y3[i]))||((x3[i]==x2[i])&&(y3[i]==y2[i]))) break;
     //x1[i]==0)&&(x2[i]==0)&&(x3[i]==0)&&(y1[i]==0)&&(y2[i]==0)&&(y3[i]==0
   }

     for(i=0;i<n-1;i++)
    {
     a[i]=godistance(x1[i],y1[i],x2[i],y2[i]);
     b[i]=godistance(x2[i],y2[i],x3[i],y3[i]);
     c[i]=godistance(x1[i],y1[i],x3[i],y3[i]);

     p=(a[i]+b[i]+c[i])/2;

     s=sqrt(p*(p-a[i])*(p-b[i])*(p-c[i]));

     printf("%0.1f\n",s);
    }

   return 0;
}

double godistance(int x1,int y1,int x2,int y2)
{
    double d;
    d=sqrt((x1-x2)*(x1-x2)-(y1-y2)*(y1-y2));
    return d;
}