Описать функцию Area(Ax,Ay,Bx,By,Cx,Cy) находящую площадь треугольника

void two(int A, int B, int C, int D, int P) {
    double res, SABC;
    SABC = sqrt(P*(P-abs(A*B)*(P-abs(A*C))*(P-abs(B*C))));

#include <iostream>
#include <cmath>
using namespace std;
 
struct point {
    double x;
    double y;
};
 
double S(point A, point B, point C) 
{
    double AB = sqrt((A.x - B.x) * (A.x - B.x) + (A.y - B.y) * (A.y - B.y));
    double BC = sqrt((B.x - C.x) * (B.x - C.x) + (B.y - C.y) * (B.y - C.y));
    double CA = sqrt((C.x - A.x) * (C.x - A.x) + (C.y - A.y) * (C.y - A.y));
    double p = (AB + BC + CA) / 2.0;
    double sABC = sqrt(p * (p - AB) * (p - BC) * (p - CA));
    return sABC;
}
 
int main()
{
    point A, B, C, D;
    cout << "Enter point A:" << endl;
    cout << "\txA = "; cin >> A.x;
    cout << "\tyA = "; cin >> A.y;
    cout << "Enter point B:" << endl;
    cout << "\txB = "; cin >> B.x;
    cout << "\tyB = "; cin >> B.y;
    cout << "Enter point C:" << endl;
    cout << "\txC = "; cin >> C.x;
    cout << "\tyC = "; cin >> C.y;
    cout << "Enter point D:" << endl;
    cout << "\txD = "; cin >> D.x;
    cout << "\tyD = "; cin >> D.y;
 
    double sABC = S(A, B, C);
    cout << "sABC = " << sABC << endl;
    double sABD = S(A, B, D);
    cout << "sABD = " << sABD << endl;
    double sACD = S(A, C, D);
    cout << "sACD = " << sACD << endl;
 
    system("pause");
    return 0;
}