已知三个点坐标判断三角形是什么形状的C++语言怎么写啊

我帮你运行了，没有出错啊，不是只是钝角啊。#include<iostream.h>
#include<math.h>
void main()
{
double x1;
double y1;
double x2;
double y2;
double x3;
double y3;

cout << "x1=";
cin >> x1;
cout << "y1=";
cin >> y1;
cout << "x2=";
cin >> x2;
cout << "y2=";
cin >> y2;
cout << "x3=";
cin >> x3;
cout << "y3=";
cin >> y3;

double z1=sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
double z2=sqrt((x2-x3)*(x2-x3)+(y2-y3)*(y2-y3));
double z3=sqrt((x3-x1)*(x3-x1)+(y3-y1)*(y3-y1));
double p=(z1+z2+z3)/2;
double s=sqrt(p*(p-z1)*(p-z2)*(p-z3));
double a=(z1*z1+z2*z2-z3*z3);
double b=(z2*z2+z3*z3-z1*z1);
double c=(z3*z3+z1*z1-z2*z2);

cout << "面积s=" << s << end