import java.util.*;
import java.io.*;
public class ArrayStuff{
private int[] a;
private Random r = new Random();
public ArrayStuff() {
a=new int[20];
for (int i=0;i<a.length;i++) {
a[i]=r.nextInt(100);
}
}
public String toString() {
return Arrays.toString(a);
}
// return the index of the max element
public int findMaxIndex() {
if (a==null || a.length==0)
return -1;
int maxi = 0;
for (int i=0;i<a.length;i++) {
if (a[i] > a[maxi])
maxi = i;
}
return maxi;
}
public int get(int n) {
if (n>=0 && n < a.length)
return a[n];
else
return -1;
}
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 x = 0;
for (int i=0; i < a.length; i = i + 1){
x = x + a[i];
}
x = x/a.length;
return x;
}
public double stddev(){
double x = 0;
double y = mean();
for (int i = 0; i < a.length; i = i + 1){
x = x + ((a[i] - y) * (a[i] - y));
}
x = x/a.length;
x = Math.sqrt(x);
return x;
}
}