Array headache

Question

I am trying to create a histogram using 2 arrays. One stores the user input and the other categorizes the input into 10 different "buckets" i.e. 1 - 10; 11 - 20, etc.
I almost have it but when I print out the histogram I get a really large number for the first category (1 - 10). It looks like I'm getting a value that is some derivation of the array.length and I have no clue why.
Does anyone have an idea what I could do to get the first category to work. The keyboard class was written by the authors of the textbook we're using.
here is what I have so far:
import cs1.Keyboard;
public class Histogram
public static void main (String[] args)
final int MIN = 1;
final int MAX = 100;
int input = 0;
int index = 0;
float category = 0;
float[] numbers = new float[1000];
int[] frequency = new int[10];
while (input != -1 && (index < numbers.length))     
System.out.print ("Enter a number between " + MIN + " and " + MAX + " (-1 to summarize): ");
input = Keyboard.readInt();
if (input != -1 && (input < MIN || input > MAX))
System.out.println ("The number you entered an invalid value!");
System.out.println ("Please enter a value between " + MIN + " and " + MAX);
else
numbers[index] = input;
index++;     
if (input == -1)
for (int i = 0; i < numbers.length; i++)
if ((numbers[i] % 10 == 0) && (numbers[i] / 10 != 10))
//category = ((numbers[i] / 10) - 1);
category = (numbers[i] / 10);
else
if (numbers[i] / 10 == 10)
category = 9;
else
if (numbers[i] / 10 < 1)
category = 0;
else
category = numbers[i] / 10;
frequency[(int)category] = frequency[(int)category] + 1;
for (int i = 0; i < frequency.length; i++)
System.out.println (i + "1 - " + (i + 1) + "0 | " + frequency);

Answer 1

Try to change the output section like this:
From:
for (int i = 0; i < frequency.length; i++)
System.out.println (i + "1 - " + (i + 1) + "0 | " + frequency[ i ]);
To:
int k=1;
for (int i = 0; i < frequency.length; i++) {
     String out=""+k;
     if (out.length()<2) out=" "+out;
     k+=10;
     String tmp=""+(k-1);
     while (tmp.length()<3) tmp=" "+tmp;
     out+=" - "+tmp+" | ";
     for (int j=0;j<frequency[ i ];j++) out+="*";
     System.out.println (out);
};o)
V.V.