
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    }
} import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    } main {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        } 0 == 0 0 0 {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        } int ninzu = scanner.nextInt(); ninzu scanner.nextInt() scanner.nextInt scanner if (ninzu == 0) {
                break;
            } ninzu == 0 ninzu 0 {
                break;
            } break; double[] tensu = new double[ninzu]; tensu new double[ninzu] ninzu for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            } int i = 0; int i = 0; i 0 ninzu > i ninzu i i++ i++ i {
                tensu[i] = scanner.nextInt();
            } {
                tensu[i] = scanner.nextInt();
            } tensu[i] = scanner.nextInt() tensu[i] tensu i scanner.nextInt() scanner.nextInt scanner double goukei = 0; goukei 0 for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            } int i = 0; int i = 0; i 0 ninzu > i ninzu i i++ i++ i {
                goukei += tensu[i];
            } {
                goukei += tensu[i];
            } goukei += tensu[i] goukei tensu[i] tensu i double heikin = goukei / ninzu; heikin goukei / ninzu goukei ninzu double bunsan = 0; bunsan 0 for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            } int i = 0; int i = 0; i 0 ninzu > i ninzu i i++ i++ i {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            } {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            } bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu bunsan (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu (tensu[i] - heikin) * (tensu[i] - heikin) (tensu[i] - heikin) tensu[i] tensu i heikin (tensu[i] - heikin) tensu[i] tensu i heikin ninzu double bunsan2; bunsan2 bunsan2 = Math.sqrt(bunsan) bunsan2 Math.sqrt(bunsan) Math.sqrt Math bunsan System.out.println(bunsan2) System.out.println System.out System System.out bunsan2 String[] args args public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    }
} public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    }
} Main

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        while (0 == 0) {

            int ninzu = scanner.nextInt();
            if (ninzu == 0) {
                break;
            }
            double[] tensu = new double[ninzu];

            for (int i = 0; ninzu > i; i++) {
                tensu[i] = scanner.nextInt();
            }

            double goukei = 0;

            for (int i = 0; ninzu > i; i++) {
                goukei += tensu[i];
            }

            double heikin = goukei / ninzu;

            double bunsan = 0;

            for (int i = 0; ninzu > i; i++) {
                bunsan += (tensu[i] - heikin) * (tensu[i] - heikin) / ninzu;
            }
            double bunsan2;
            bunsan2 = Math.sqrt(bunsan);

            System.out.println(bunsan2);
        }
    }
}