#include <iostream>
#include <iomanip>
#include <cmath>

int main()
{ 
	using namespace std;
	
	double start=-2, end=0, step=0.2;
	size_t n=size_t((end-start)/step)+1;
	
	cout << fixed << setprecision(3);
	
	for (size_t i=0; i != n; ++i) {
	  double x = start+i*step;
	  double y = atan(sqrt(x*x+1));
	  cout << "x = " << x << "\ty = " << y << endl;
	}
}