cpp 2

#include <iostream>
#include <Windows.h>
#include <cmath>
using namespace std;

int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(0);
    setlocale(LC_ALL, "Russian");
    SetConsoleCP(1251);
    SetConsoleOutputCP(1251);

    int Ax, Ay, Bx, By, Cx, Cy, Dx, Dy;
    cin >> Ax >> Ay >> Bx >> By >> Cx >> Cy >> Dx >> Dy;

    double ab = sqrt((Bx - Ax) * (Bx - Ax) + (By - Ay) * (By - Ay));
    double bc = sqrt((Cx - Bx) * (Cx - Bx) + (Cy - By) * (Cy - By));
    double cd = sqrt((Dx - Cx) * (Dx - Cx) + (Dy - Cy) * (Dy - Cy));
    double ad = sqrt((Ax - Dx) * (Ax - Dx) + (Ay - Dy) * (Ay - Dy));
    double ac = sqrt(pow(Cx - Ax, 2) + pow(Cy - Ay, 2));
    double bd = sqrt(pow(Bx - Dx, 2) + pow(By - Dy, 2));
    double eps = 1e-10;

    if (abs(ab - bc) < eps && abs(bc - cd) < eps && abs(cd - ad) < eps && abs(ad - ab) < eps) {
        if (abs(ac - bd) < eps) {
            cout << "Квадрат" << endl;
            double p = ab + bc + cd + ad;
            double s = ab * bc;
            cout << "Периметр = " << p << endl;
            cout << "Площадь = " << s << endl;
        }
        else {
            cout << "Ромб" << endl;
            double p = ab + bc + cd + ad;
            double s = 0.5 * ac * bd;
            cout << "Периметр = " << p << endl;
            cout << "Площадь = " << s << endl;
        }
    }
    else if (abs(ab - cd) < eps && abs(bc - ad) < eps && abs(ab - bc) > eps) {
        if (abs(ac - bd) < eps) {
            cout << "Прямоугольник" << endl;
            double p = ab + bc + cd + ad;
            double s = ab * bc;
            cout << "Периметр = " << p << endl;
            cout << "Площадь = " << s << endl;
        }
        else {
            cout << "Параллелограмм" << endl;
        }
    }
    else {
        cout << "Не параллелограмм" << endl;
    }
}