задача на С++

If compiling as C++:
#define _USE_MATH_DEFINES
#include <cmath>
If compiling as C:
#define _USE_MATH_DEFINES
#include <math.h>
#include <iostream>
#include <stdafx.h>
int _tmain(int argc, _TCHAR* argv[]);
double a,b,c,alfa,beta,gamma;
const long double M_PI = 3.14;
int main();
{
    cout<<"введите данные";
    cin>>a>>b>>c;
    double p=(a+b+c)/2;
    double S=sqrt(p*(p-a)*(p-b)*(p-c));
    alfa=asin(2*S/(a*b))*180/M_PI;
    beta=asin(2*S/(b*c))*180/M_PI;
    gamma=asin(2*S/(c*b))*180/M_PI;
    cout<<"alfa="<<alfa<<" beta="<<beta<<" gamma="<<gamma;
    return 0;

#include <stdafx.h>
#include <iostream>
#include <math.h>
using namespace std;
 
int main()
{
   double a, b, c, alfa, beta, gamma, PI = 3.14;
 
   cout << "Number 1: ";
   cin >> a;
   cout << "Number 2: ";
   cin >> b;
   cout << "Number 3: ";
   cin >> c;
   double p = (a + b + c) / 2;
   double S = sqrt(p * (p - a) * (p - b) * (p - c));
   alfa = asin(2 * S / (a * b)) * 180 / PI;
   beta = asin(2 * S / (b * c)) * 180 / PI;
   gamma = asin(2 * S / (c * b)) * 180 / PI;
   cout<<"\nAlfa = " << alfa << "\nBeta = " << beta << "\nGamma = " << gamma <<endl;
   cin >> a;
   return 0;
}