#include<iostream>
#include<cmath>
#include<iomanip>
using namespace std;
int main(){
    float a,b;
    const float g=9.81;
    const double pi=3.14159265358979323846;
    cin>>a;
    cin>>b;
    if(a<0 || b<-90 || b>90){
        cout<<"Invalid input";
        return 0;
    }
    float s=b*pi/180;
    float h=(pow(a,2)* pow(sin(s),2) /(2*g);
    cout<<fixed<<setprecision(2)<<h;
    return 0;
}