import java.util.*;
import java.io.*;
import java.math.*;
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(){
int total = 0;
for(int i=0;i<a.length;i++){
total = total + a[i];
}
return total/a.length;
}
public double stddev(){
double avg = mean();
double sumOfDiff = 0;
for(int i=0;i<a.length;i++){
sumOfDiff = sumOfDiff+a[i]-avg;
}
double avg2=sumOfDiff/a.length;
return Math.sqrt(avg2);
}
}