import java.util.Scanner;
public class Main {

    public static void main(String[] args) {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    }
}
 import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    }
} Main public static void main(String[] args) {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    } main {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    } double sum = 0; sum 0 int n; n double s = 0; s 0 double sum1 = 0; sum1 0 try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        } {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        } Scanner sc = new Scanner(System.in) Scanner sc = new Scanner(System.in) new Scanner(System.in) while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            } true {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            } n = sc.nextInt() n sc.nextInt() sc.nextInt sc if (n == 0) {
                    break;
                } n == 0 n 0 {
                    break;
                } break; int[] scores = new int[n]; scores new int[n] n for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                } int i = 0; int i = 0; i 0 i < scores.length i scores.length scores scores.length i++ i++ i {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                } {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                } scores[i] = sc.nextInt() scores[i] scores i sc.nextInt() sc.nextInt sc sum = sum + (double)scores[i] sum sum + (double)scores[i] sum (double)scores[i] scores i double average = 0 average 0 variance = 0; variance 0 average = sum / (double)n average sum / (double)n sum (double)n for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                } int j = 0; int j = 0; j 0 j < scores.length j scores.length scores scores.length j++ j++ j {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                } {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                } sum1 = ((double)scores[j] - average) * ((double)scores[j] - average) sum1 ((double)scores[j] - average) * ((double)scores[j] - average) ((double)scores[j] - average) (double)scores[j] scores j average ((double)scores[j] - average) (double)scores[j] scores j average s = s + sum1 s s + sum1 s sum1 variance = s / n variance s / n s n System.out.println(Math.sqrt(variance)) System.out.println System.out System System.out Math.sqrt(variance) Math.sqrt Math variance sum=0 sum 0 s=0 s 0 String[] args args public class Main {

    public static void main(String[] args) {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    }
} public class Main {

    public static void main(String[] args) {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    }
} Main
import java.util.Scanner;
public class Main {

    public static void main(String[] args) {
        double sum = 0;
        int n;
        double s = 0;
        double sum1 = 0;
        try (Scanner sc = new Scanner(System.in)) {
            while (true) {
                n = sc.nextInt();
                if (n == 0) {
                    break;
                }
                int[] scores = new int[n];
                for (int i = 0; i < scores.length; i++) {
                    scores[i] = sc.nextInt();
                    sum = sum + (double)scores[i];
                }

                double average = 0, variance = 0;
                average = sum / (double)n;

                for (int j = 0; j < scores.length; j++) {
                    sum1 = ((double)scores[j] - average) * ((double)scores[j] - average);
                    s = s + sum1;
                    variance = s / n;
                }

                System.out.println(Math.sqrt(variance));
                sum=0;
                s=0;
            }
        }
    }
}

