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(){
int sum = 0;
for (int i = 0; i <a.length; i++){
sum = sum + a[i];
}
double avg = 0;
avg = sum/ a.length;
return avg;
}
public double stddev(){
double mean = this.mean();
double sum = 0;
double sq = 0;
for (int i = 0; i< a.length; i++){
sq = Math.pow(a[i]-mean,2);
}
double mean2 = sq/a.length;
double stddev = Math.sqrt(mean2);
return stddev;
}
}