#include<iostream>
#include<cmath>
#include<vector>
#include<stack>
#include<queue>
#include<set>
#include<algorithm>
#include<string>

#define x first
#define y second
#define SP system("pause")

using namespace std;

int main()
{
    double a, b, c;
    cin >> a >> b >> c;

    printf( "%.4f", 0 );

    return 0;
}