import java.io.*;
import java.util.*;
public class ArrayStuff {
private int[] a;
private Random r;
public ArrayStuff() {
r = new Random();
a = new int[20];
for (int i=0;i<a.length;i++)
a[i]=r.nextInt(100);
}
public String toString() {
return Arrays.toString(a);
}
public int get(int n) {
return a[n];
}
public int findMaxIndex() {
int maxi = 0;
for (int i=0;i<a.length;i++) {
if (a[i]>a[maxi])
maxi=i;
}
return maxi;
}
public int find(int n) {
for (int i=0;i<a.length;i++) {
if (a[i]==n)
return i;
}
return -1;
}
public double mean(){
double ans = 0;
int i;
int len = a.length;
for (i=0;i<len;i++){
ans = ans + (double)a[i];
}
return ans/(double)len;
}
public double stddev(){
int x = mean(a);
int[] second = new int[a.length];
for (int i = 0; i < a.length; i++){
second[i] = Math.pow(a[i] - x, 2);}
int y = mean(second);
int z = Math.pow(y, 0.5);
return z;
}
}