[kish1122]

#include "stdafx.h"
#include "iostream"
#include "conio.h"
#include "math.h"
double p (double a , double b , double c)
{ double p;
p=(a+b+c)/2;
return p;
};
double S (double a, double b , double c )
{double S; double pp;
pp=p(a,b,c);
S=sqrt(pp*(pp-a)*(pp-b)*(pp-c));
return S ;
};

int _tmain(int argc, _TCHAR* argv[])

{double Ax , Ay , Bx , By , Cx , Cy ;
double a,b,c,ABC,BAC,ACB;
std::cout<<"Ax=";
std::cin>>Ax;
std::cout<<"Ay=";
std::cin>>Ay;
std::cout<<"Bx=";
std::cin>>Bx;
std::cout<<"By=";
std::cin>>By;
std::cout<<"Cx=";
std::cin>>Cx;
std::cout<<"Cy=";
std::cin>>Cy;
a=sqrt((Cx-Bx)*(Cx-Bx)+(Cy-By)*(Cy-By));
b=sqrt((Cx-Ax)*(Cx-Ax)+(Cy-Ay)*(Cy-Ay));
c=sqrt((Ax-Bx)*(Ax-Bx)+(Ay-By)*(Ay-By));
ABC=((Cx-Bx)*(Ax-Bx)+(Cy-By)*(Ay-By))/(a*c);
BAC=((Cx-Ax)*(Bx-Ax)+(Cy-Ay)*(By-Ay))/(b*c);
ACB=((Bx-Cx)*(Ax-Cx)+(By-Cy)*(Ay-Cy))/(b*a);
if (ABC<0||BAC<0||ACB<0){
std::cout<<"Obtuse angle"<<std::endl;}
else
if (ABC==0||BAC==0||ACB==0){
std::cout<<"Rectangle "<<std::endl;}
else std::cout<<"Sharp angle"<<std::endl;

std::cout<<"Semiperimetr = "<<p(a,b,c)<<std::endl;
//std::cout<<a<<std::endl;
//std::cout<<b<<std::endl; std::cout<<c<<std::endl;
std::cout<<"Square of Triangle = ";
std::cout<<S(a,b,c);
getch();
return 0;

}

std::cout<<"Semiperimetr = "<<p(a,b,c)<<std::endl; //std::cout<<a<<std::endl; //std::cout<<b<<std::endl; std::cout<<c<<std::endl; std::cout<<"Square of Triangle = "; »

причем вот это учителю было не важно!!!!