Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to generate random values that won’t repeat in Java
To generate random values that won’t repeat, use HashSet collection. Firstly, create a random object and HashSet −
Random randNum = new Random(); Set<Integer>s = new HashSet<Integer>();
Now, add random integers −
while (s.size() < 10) {
s.add(randNum.nextInt());
}Now, display the random numbers that are unique −
List<Integer>list = new ArrayList<Integer>(s); System.out.println(list);
Example
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Set;
import java.util.Random;
import java.util.List;
public class Demo {
public static void main(String[] args) {
Random randNum = new Random();
Set<Integer>s = new HashSet<Integer>();
while (s.size() < 10) {
s.add(randNum.nextInt());
}
System.out.println("Random numbers that aren't repeating...");
List<Integer>list = new ArrayList<Integer>(s);
System.out.println(list);
}
}Output
Random numbers that aren't repeating... [-951684393, -2119833673, 1804429247, -1389537752, -1314261216, 575783898, 326063891, -1241554605, -613888875, -1698001241]
Let us see another example to get distinct random numbers that won’t repeat −
Random numbers that aren't repeating... [1173054490, -613376175, -1947139369, -840397233, 931136232, 135129829, 1634496580, 13228721, 1929509800, 1205305181]
Updated on: 30-Jul-2019
283 Views
Advertisements