/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{

	float x = 9;

	float result = sqrt(x);

	System.out.println(result);

	}

	public static float sqrt(float x) {
		float y = 1;
		int two = 2;
		float temp1 = 0;
		float temp2 = 0;
		float z = 0;
		while (y != z) {
			z = y;
			temp1 = x/y;
			temp2 = temp1 + y;
			y = temp2/two;
		}

		return(y);

	}

}