Fibonacci Series in C

The Fibonacci series is a well-known mathematical series, In this article, we are going to write a C program that prints n numbers of the Fibonacci series.

Fibonacci Series

Fibonacci series is characterized by recurrence relation, each term/element/number is the sum of two previous terms/element/number, Starting from 0 and 1. An example of the Fibonacci series is given below-

0,1,1,2,3,5,8,13,21,……..

C Program to Print Fibonacci Series

In C we can print the Fibonacci series either by using an iterative approach or using recursive approach

Iterative Approach to Print Fibonacci Series

We are going to print the Fibonacci series in C by using loops.

#include <stdio.h>
void main()
{
    int first = 0, second = 1, next, n;
    printf("Enter the number of elemnet for the Fibonacci series");
    scanf("%d", &n);
    for (int i = 1; i <= n; i++)
    {
        printf("%d  ", first);
        next = first + second;
        first = second;
        second = next;
    }
}

Output

Fibonacci Series Using Recursion in C

#include <stdio.h>
int fibonacci(int n)
{
    if (n <= 1)
    {
        return n;
    }
    else
    {
        return fibonacci(n - 1) + fibonacci(n - 2);
    }
}
void main()
{
    int first = 0, second = 1, next, n;
    printf("Enter the number of elemnet for the Fibonacci series");
    scanf("%d", &n);
    for (int i = 0; i <= n; i++)
    {
        printf("%d  ", fibonacci(i));
    }
}

Output

Happy Coding

See Also

• Multipling Floating Point Numbers in C
• Area of Square in C