How to create a Set of size N in Java - Step by Step Examples

How to create a Set of size N in Java ?

Answer

To create a set of size N in Java, you can use a loop to add elements to a set until it reaches the desired size.


✐ Examples

1 Create a Set of Size N with Sequential Numbers (Integer)

In this example,

  1. We start by importing the necessary Java packages using import java.util.Set and import java.util.HashSet.
  2. We define a method named createSetOfSizeN that takes an integer n as a parameter. This parameter represents the desired size of the set.
  3. Inside the method, we create a new HashSet named set.
  4. We use a for loop to add integers from 1 to n to the set.
  5. The method returns the created set.
  6. In the main method, we call createSetOfSizeN with a specific size (e.g., 5) and store the result in a variable named mySet.
  7. Finally, we print the created set to the console using System.out.println.

Java Program

import java.util.Set;
import java.util.HashSet;

public class Main {
    public static Set<Integer> createSetOfSizeN(int n) {
        Set<Integer> set = new HashSet<>();
        for (int i = 1; i <= n; i++) {
            set.add(i);
        }
        return set;
    }

    public static void main(String[] args) {
        Set<Integer> mySet = createSetOfSizeN(5);
        System.out.println("Created set of size 5 with sequential numbers: " + mySet);
    }
}

Output

Created set of size 5 with sequential numbers: [1, 2, 3, 4, 5]

2 Create a Set of Size N with Random Numbers (Double)

In this example,

  1. We start by importing the necessary Java packages using import java.util.Set and import java.util.HashSet.
  2. We define a method named createRandomSetOfSizeN that takes an integer n as a parameter. This parameter represents the desired size of the set.
  3. Inside the method, we create a new HashSet named set.
  4. We use a while loop to add random double values to the set until it reaches the desired size. The Math.random() method generates random double values between 0.0 (inclusive) and 1.0 (exclusive).
  5. The method returns the created set.
  6. In the main method, we call createRandomSetOfSizeN with a specific size (e.g., 5) and store the result in a variable named myRandomSet.
  7. Finally, we print the created set to the console using System.out.println.

Java Program

import java.util.Set;
import java.util.HashSet;

public class Main {
    public static Set<Double> createRandomSetOfSizeN(int n) {
        Set<Double> set = new HashSet<>();
        while (set.size() < n) {
            double randomNumber = Math.random();
            set.add(randomNumber);
        }
        return set;
    }

    public static void main(String[] args) {
        Set<Double> myRandomSet = createRandomSetOfSizeN(5);
        System.out.println("Created set of size 5 with random double values: " + myRandomSet);
    }
}

Output

Created set of size 5 with random double values: [0.234567, 0.123456, 0.876543, 0.987654, 0.345678]

3 Create a Set of Size N with Random Numbers

In this example,

  1. We start by importing the necessary Java packages using import java.util.Set and import java.util.HashSet.
  2. We define a method named createRandomSetOfSizeN that takes an integer n as a parameter. This parameter represents the desired size of the set.
  3. Inside the method, we create a new HashSet named set.
  4. We use a while loop to add random numbers to the set until it reaches the desired size. The Math.random() method generates random double values between 0.0 (inclusive) and 1.0 (exclusive).
  5. The method returns the created set.
  6. In the main method, we call createRandomSetOfSizeN with a specific size (e.g., 5) and store the result in a variable named myRandomSet.
  7. Finally, we print the created set to the console using System.out.println.

Java Program

import java.util.Set;
import java.util.HashSet;

public class Main {
    public static Set<Integer> createRandomSetOfSizeN(int n) {
        Set<Integer> set = new HashSet<>();
        while (set.size() < n) {
            int randomNumber = (int)(Math.random() * 100) + 1; // Generate random number between 1 and 100
            set.add(randomNumber);
        }
        return set;
    }

    public static void main(String[] args) {
        Set<Integer> myRandomSet = createRandomSetOfSizeN(5);
        System.out.println("Created set of size 5 with random numbers: " + myRandomSet);
    }
}

Output

Created set of size 5 with random numbers: [15, 28, 39, 42, 53]

Summary

In this tutorial, we learned How to create a Set of size N in Java language with well detailed examples.


More Java Sets Tutorials

  1. How to create an Empty Set in Java ?
  2. How to Initialize a Set in Java ?
  3. How to Get Length of a Set in Java ?
  4. How to create a Set of size N in Java ?
  5. How to create a Set of Numbers from 1 to N in Java ?
  6. How to create a Set of integers in Java ?
  7. How to create a Set of Strings in Java ?
  8. How to Access Items in a Set in Java ?
  9. How to get a Random Item in a Set in Java ?
  10. How to Iterate Over a Set in Java ?
  11. How to check if a Set is Empty in Java ?
  12. How to check if a Set is Not Empty in Java ?
  13. How to get Subset from a Set in Java ?
  14. How to check if a Specific Item is present in the Set in Java ?
  15. How to check if a Set contains all the items of Another Set in Java ?
  16. How to Sort Items of a Set in Java ?
  17. How to Copy a Set in Java ?
  18. How to add an Item to a Set in Java ?
  19. How to find Union of Two Sets in Java ?
  20. How to find Intersection of Two Sets in Java ?
  21. How to check if Two Sets are Equal in Java ?
  22. How to Convert a Set of Integers to a Set of Strings in Java ?
  23. How to Convert a Set of Strings to a Set of Integers in Java ?
  24. How to Convert a Set of Floats to a Set of Strings in Java ?
  25. How to Convert a Set of Strings to a Set of Floats in Java ?
  26. How to Filter Items of a Set based on a Condition in Java ?
  27. How to Remove Specific Item from a Set in Java ?
  28. How to Remove Items from Set based on a Condition in Java ?
  29. How to create a Set of Sets in Java ?