# How to calculate the possibilities of duplication for random number within a range in Java

To get the duplicate numbers for random numbers in a range, loop through and create two Random class objects −

Use nextInt() to get the next number −

intrandVal1 = new Random().nextInt(50);
intrandVal2 = new Random().nextInt(50);

Now, compare both the above numbers −

if (randVal1 == randVal2) {
System.out.println("Duplicate number = "+randVal1);
}

All the above is to be done in a loop −

for (int i = 1; i <= 50; i++) {
intrandVal1 = new Random().nextInt(50);
intrandVal2 = new Random().nextInt(50);
if (randVal1 == randVal2) {
System.out.println("Duplicate number = "+randVal1);
}
}

## Example

import java.util.Random;
public class Demo {
public static void main(String[] args) {
for (int i = 1; i<= 50; i++) {
int randVal1 = new Random().nextInt(50);
int randVal2 = new Random().nextInt(50);
if (randVal1 == randVal2) {
System.out.println("Duplicate number = "+randVal1);
}
}
}
}

## Output

Duplicate number = 35
Duplicate number = 28