#include <iostream>
#include <fstream>
#include <cmath>

using namespace std;

double f(double x){
    return x + 4 / (x + 0.3) - sin(x) - 3;
}

double max1(double a, double b, double h){
    ifstream input("output.txt");
    double x = a;
    double m;
    while (x <= b){
        double b;
        input >> b;
        if (x == a){
            input >> m;
        }else{
            double val;
            input >> val;
            if (val > m){
                m = val;
            }
        }
        x += h;
    }
    return m;
}
int main()
{
    double a, b, h;
    cin >> a >> b >> h;
    ofstream output("output.txt");
    double x = a;
    while ( x <= b){
        output << x << " " << f(x) << endl;
        x += h;
    }
    cout << max1(a, b, h);
}