Using Arrays to Store Fibonacci Numbers in Java

 

The Fibonacci Series is a classic sequence where each number is the sum of the two preceding ones. In Java, one efficient way to generate and store the Fibonacci numbers is by using arrays. This approach helps when you want to access any Fibonacci number multiple times without recalculating it.

In this blog, we’ll discuss how to implement a Fibonacci Series program in Java using arrays.

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What Is the Fibonacci Series?

The Fibonacci sequence starts like this:

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ...

Every number is calculated as:
F(n) = F(n-1) + F(n-2)

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Why Use Arrays?

Using arrays to store Fibonacci numbers allows you to:

• Store all the computed numbers in memory for quick access.

• Avoid redundant calculations, especially useful for larger sequences.

• Easily print or manipulate the entire sequence later.

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Java Program to Store Fibonacci Numbers in an Array

public class FibonacciWithArray {

    public static void main(String[] args) {
        int n = 10;  // Number of Fibonacci terms to generate
        int[] fibonacci = new int[n];

        // Initialize the first two terms
        fibonacci[0] = 0;
        fibonacci[1] = 1;

        // Calculate the remaining Fibonacci numbers and store them in the array
        for (int i = 2; i < n; i++) {
            fibonacci[i] = fibonacci[i - 1] + fibonacci[i - 2];
        }

        // Print the Fibonacci series stored in the array
        System.out.println("Fibonacci Series up to " + n + " terms:");
        for (int num : fibonacci) {
            System.out.print(num + " ");
        }
    }
}

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How It Works

1. We declare an integer array fibonacci of size n to store the numbers.

2. The first two elements of the array are initialized to 0 and 1, the first two Fibonacci numbers.

3. Using a for loop starting from index 2, each subsequent number is calculated as the sum of the two previous numbers and stored in the array.

4. Finally, we print all numbers stored in the array.

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Output

Fibonacci Series up to 10 terms:
0 1 1 2 3 5 8 13 21 34

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Benefits of Using Arrays for Fibonacci Numbers

• Efficiency: Once calculated, each Fibonacci number is stored and can be accessed instantly.

• Flexibility: You can use the array for further processing, such as finding the sum, average, or filtering the sequence.

• Clarity: The code structure is simple and easy to follow, especially for those learning Java arrays.

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Conclusion

Storing Fibonacci numbers in an array is a practical approach for generating and working with Fibonacci sequences in Java. It combines simplicity with efficient access to previously computed values, making it ideal for many applications.

If you want to explore more ways to write the Fibonacci Series program in Java, including recursive or dynamic programming approaches, stay tuned for upcoming tutorials!