#include <bits/stdc++.h>

using namespace std;

const double pi=3.14159265359;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    double a,b,z;
    cin>>a>>b>>z;
    if(z==90) {cout<<fixed<<setprecision(3)<<b*a*sqrt(2); return 0;}
    z=z*pi/180;
    double a1=a*sqrt(2.0);
    double a2=2*(a*sqrt(2.0)/2-(b*cos(z)/sin(z)));
    a2=max(0.0,a2);
    double h0=min(b/sin(z),(a1/2)/cos(z));
    cout<<fixed<<setprecision(3)<<(a1+a2)/2*h0;

}