Untitled

#include <iostream>
#include <fstream>
using namespace std;
float V(float a, float b, float h) {
	float v;
	v = a * b * 0.3333333 * h;
	return v;
}
int main()
{
	ifstream in("input.txt");
	float a, b, h, v;
	in >> a >> b >> h;
	cout << fixed;

	cout.precision(2);
	v = V(a,b,h);
	cout << v;

}