//---------------------------------------------------------------------
//  Sınislausn á dæmi 5 á Vikublaği 1 í Tölvunarfræği 2, vor 2005
//
//  Hjálmtır Hafsteinsson, janúar 2005
//---------------------------------------------------------------------
#include <iostream>
#include <cmath>
using namespace std;

const double SKEKKJA = 0.000001;

int main()
{
	double x, r, r_old;

	cout << "Sladu inn x ";
	cin >> x;

	r_old = x/2.0;
	r = x;

	while( fabs( (r - r_old)/r ) > SKEKKJA ) {
		r_old = r;
		r = ( r_old + x/r_old ) / 2.0;
	}

	cout << "Nalgun a kvadratrot " << x << " er " << r << endl;

	return 0;
}