/* 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
	{
		Scanner in = new Scanner(System.in);
 
		int n = in.nextInt();
 
		double a, p=1, k;
 
		for(int i=1; i<=n; i++){
			a = in.nextDouble();
			p*=a;
		}
		k=Math.sqrt(Math.abs(p));
		System.out.println(k);
	}
}

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

NCAtNSAyIDQgLTMuNg==

4 -5 2 4 -3.6