lab1_2

#include "stdafx.h"
#include <iostream>
#include <cmath>
using namespace std;
//
int _tmain(int argc, _TCHAR* argv[])
{
	const float PI = 3.14F;
	double rad, diam, len, ar;
	char ans;
	cout << "What value do you want to set? Radius(r), Diameter(d), Length(l) or Area(a):  ";
	cin >> ans;
	switch (ans)
	{
	case 'r': 
		cout << "Enter value: ";
		cin >> rad;
		cout << "2 - Diameter: " << rad * 2        << endl;
		cout << "3 - Length: "   << rad * 2 * PI   << endl;
		cout << "4 - Area: "     << rad * rad * PI << endl;
		break;
	case 'd':
		cout << "Enter value: ";
		cin >> diam;
		rad = diam / 2;
		len = diam * PI;
		ar = rad * rad * PI;
		cout << "1 - Radius: "   << rad << endl;
		cout << "3 - Length: "   << len << endl;
		cout << "4 - Area: "     << ar  << endl;
		break;
	case 'l':
		cout << "Enter value: ";
		cin >> len;
		rad = len / (2 * PI);
		diam = len / PI;
		ar = rad * rad * PI;
		cout << "1 - Radius: "   << rad  << endl;
		cout << "2 - Diameter: " << diam << endl;
		cout << "4 - Area: "     << ar   << endl;
		break;
	case 'a':
		cout << "Enter value: ";
		cin >> ar;
		rad = sqrt(ar / PI);
		diam = rad * 2;
		len = diam * PI;
		cout << "1 - Radius: "   << rad   << endl;
		cout << "2 - Diameter: " << diam  << endl;
		cout << "3 - Length: "   << len   << endl;
		break;
	}
	system("PAUSE");
	return 0;
}