ArrayStuff.java

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 int[] getArray() {
	return a;
    }

    public double mean(int[] a) {
	double answer = 0;
	double sum = 0;
	for (int i = 0; i < a.length; i++) {
	    sum = sum + a[i];
	}
	answer = sum/a.length;
	return answer;
    }

    public double stddev(int[] a) {
	double answer = 0;
	double sum = 0;
	double mean = this.mean(a);
	for (int i = 0; i < a.length; i++) {
	    double z = (a[i] - mean) * (a[i] - mean);
	    sum = sum + z;
	}
	answer = Math.sqrt(sum);
	return answer;
    }
	
}