Definition of Fibonacci numbers:

We assume first two Fibonacci are 0 and 1
A series of numbers in which each sequent number is sum of its two previous numbers is known as Fibonacci series and each numbers are called Fibonacci numbers. So Fibonacci numbers is

Example of Fibonacci series:

0 , 1 ,1 , 2 , 3 , 5 , 8 , 13 , 21 , 34 , 55  ...


1. Write a program to generate the Fibonacci series in c

#include<stdio.h>
#include<conio.h>

int main()
{
    int k,r;
    long int i=0l,j=1,f;

    //Enter max and min number
    printf("Enter the number range:");
    scanf("%d",&r);

    printf("FIBONACCI SERIES: ");
    printf("%ld %ld",i,j); //printing firts two values.

    for(k=2; k<=r; k++)
    {
         f=i+j;
         i=j;
         j=f;
         printf(" %ld",j);
    }  
    return 0;
}

Sample output:
Enter the number range: 15
FIBONACCI SERIES: 0 1 1 2 3 5 8 13 21 34 55 89 144 233 377



2. Fibonacci series using array in c


#include<stdio.h>
#include<conio.h>

int main()
{

    int i,range;
    long int arr[40];

    printf("Enter the number range: ");
    scanf("%d",&range);

    arr[0]=0;
    arr[1]=1;

    for(i=2; i<=d; i++)
    {
         arr[i] = arr[i-1] + arr[i-2];
    }

    printf("Fibonacci series is: ");
    for(i=0; i<=d; i++)
    {
         printf("%ld ",arr[i]);
    }
    return 0;
}

Sample output:
Enter the number range: 20
Fibonacci series is: 0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 1597 2584 4181



1. Fibonacci series in c using while loop


#include<stdio.h>
#include<conio.h>

int main()
{
    int k=2,r;
    long int i=0l,j=1,f;

    printf("Enter the number range:");
    scanf("%d",&r);

    printf("Fibonacci series is: %ld %ld",i,j);

    while(k<=d)
    {
         f=i+j;
         i=j;
         j=f;
         printf(" %ld",j);
          k++;
    }
  
    return 0;
}


Sample output:
Enter the number range: 10
Fibonacci series is: 0 1 1 2 3 5 8 13 21 34