#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;

int main() {
	// your code goes here
	double a, b, h;
	cin >> a >> b>> h;
	for(double x = a; x <= b; x += h){
		cout << fixed << setprecision(3) <<x<< " " << 3 * sin(x) << endl;	
	}
	return 0;
}