# Unique Random Generator

 Pravin Kumar · November 15, 2015 I'm trying to get random numbers between 0 and 100. But I want them to be unique, not repeat in sequence. For example if I got 5 number. They must be 82,12,53,64,32 not like 82,12,53,12,32.``Random rand = new Random();selected = rand.nextInt(100);``

## Replies

 Jon Z. · November 15, 2015 This should do the trick.``import java.util.ArrayList;import java.util.Random;/** * @author Jon Z. * jon.zz@outlook.com */public class RandomStuff {    private final static int MAX_NUM = 100;    private static ArrayList randomNumbers = new ArrayList();        public static int getNewRandom(){        if(randomNumbers.size() >= 100){            System.out.println("Can't have more than " + MAX_NUM + " different numbers.");            return -1;        }                Random rand = new Random();        int selected = rand.nextInt(MAX_NUM);        if(isNew(selected)){            randomNumbers.add(selected);            return selected;        }        else{            return getNewRandom();        }    }        public static boolean isNew(int selected){        for (int i = 0; i < randomNumbers.size(); i++) {            if(randomNumbers.get(i) == selected){                return false;            }        }        return true;    }        public static void main(String[] args) {        for (int i = 0; i < 103; i++) {            System.out.print("Rand#" + (i+1) + " - ");            int newRand = getNewRandom();            if(newRand != -1){                System.out.println(newRand);            }        }    }    }``
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## Java / Android Development

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