#include <iostream>
#include <stdlib.h>
#include<math.h>
using namespace std;

void medie(float a, float b, float c)
{
    float MG, MA;
    MG = sqrt(a*b*c);
    cout << "MG=" << MG << endl;
    MA = (2 * a*b*c) / (a + b + c);
    cout << "MA=" << MA << endl;

}

void medie(float a, float b, float c, float d)
{
    float MG, MA;
    MG = sqrt(a*b*c*d);
    cout << "MG=" << MG << endl;
    MA = (2 * a*b*c*d) / (a + b + c + d);
    cout << "MA=" << MA << endl;
}

int main()
{
    float a, b, c, d;
    cout << "a=" << endl;
    cin >> a;
    cout << "b=" << endl;
    cin >> b;
    cout << "c=" << endl;
    cin >> c;
    cout << "d=" << endl;
    cin >> d;

    medie(a, b, c);

    medie(a, b, c, d);
}