## Pages

### Fibonacci Series Code in C#

Fibonacci series is a series of numbers where the next number is the sum of the previous two numbers behind it. It has the starting two numbers predefined as 0 & 1. The series goes on like this:
0,1,1,2,3,5,8,13,21,34,55,89,144,233,377……..

Here we illustrate two techniques for the creation of the Fibonacci Series to n terms. The For Loop method & the Recursive Technique. Check them below.

The For Loop technique requires that we create some variables and keep track of the latest two terms('First' & 'Second'). Then we calculate the next term by adding these two terms & setting a new set of two new terms. These terms are the 'Second' & 'Newest'.

namespace Fibonacci_series_Using_For_Loop
{
class Program
{
static void Main(string[] args)
{
int n, first = 0, second = 1, next, c;
Console.WriteLine("Enter the number of terms");
Console.WriteLine("First "+ n +" terms of Fibonacci series are:");
for (c = 0; c < n; c++)
{
if (c <= 1)
next = c;
else
{
next = first + second;
first = second;
second = next;
}
Console.WriteLine(next);
}
}
}
}

The recursive technique to a Fibonacci series requires the creation of a function that returns an integer sum of two new numbers. The numbers are one & two less than the number supplied. In this way final output value has each number added twice excluding 0 & 1. Check the program below.

namespace Fibonacci_Series_Recursion
{
class Program
{
static void Main(string[] args)
{
int n, i = 0, c;
Console.WriteLine("Enter the number of terms");
Console.WriteLine("First 5 terms of Fibonacci series are");
for ( c = 1 ; c <= n ; c++ )
{
Console.WriteLine(Fibonacci(i));
i++;
}