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Array Elements As Counters - JavaDevelopmentForums.com

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We're going to build a program to re-enact a dice being rolled one thousand times. We're going to output how many times each face of the dice is rolled.

import java.util.Random;
class RollDice{
   public static void main(String args[]){
	   Random rand = new Random();
	   int freq[] = new int[7];
	   for(int roll = 1; roll <= 1000; roll++){
		   ++freq[1 + rand.nextInt(6)];
	   for(int face = 1; face < freq.length; face++){
		   System.out.println(face + "\t" + freq[face]);

First of all, we have to import our random class. Then, we create a new random number object called rand. We create a new integer array called freq. We set this equal to 7 because we want the numbers 1-6. 7 Will give us 0-6 but we'll just ignore the zero.

Next up is our for loop set to iterate one thousand times. In that we increment the index of our frequency array by a random number ranging from 1 through to 6. This line of code stores the values of each face of the die.

We then output a header (face and frequency) separated by a tab and create a small for loop to output the face and value of each face. This is really just six iterations.

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