// Quiz1.java
// <your name here>

// Write a Java program that reads in the AREA of a circle
// as a double, and prints out the RADIUS of the same circle.
// Note that A = pi r^2.

class Quiz1 {
	
	public static void main(String[] args) {
		// your code here!
	}



	///////////////////////////////////
	// readString, readInt, readDouble
	///////////////////////////////////
	
	public static String readString() {
		java.io.InputStreamReader isr = new java.io.InputStreamReader(System.in);
		java.io.BufferedReader d = new java.io.BufferedReader(isr);
		try { return d.readLine(); } catch (Exception e) { return "error"; }
	}
	public static int readInt() { return Integer.parseInt(readString()); }
	public static double readDouble() {
		return Double.valueOf(readString()).doubleValue();
	}
}