# Finding Nth term of a fibonacci series in C

## Nth Term of Fibonacci Series

Today in this article we will learn about how to find the Nth term of the Fibonacci series in C language.

The Fibonacci sequence is a series of numbers in which each number is the sum of the two that precede it.

```Starting at 0 and 1 the sequence looks like :
0, 1, 1, 2, 3, 5, 8, 13, 21, 34, and so on forever``` ## Methods Discussed

• Iterative
• Recursive

Note – Fibonacci Series starts at 0th term.

`F(0) : 0F(1) : 1F(2) : 1F(3) : 2F(4) : 3F(5) : 5F(6) : 8F(7) : 13F(8) : 21F(9) : 34` ## C Code (Method 1) :-

```// C Program to print the nth term in fibonacci series
// Note : Acc to fibonacci series definition
// 0th term : 0, 1st term : 1
#include

int main() {

int a = 0, b = 1;
int nextTerm;

int n = 6;

// if asked to print 0th/1st term
// f(0) = 0 and f(1) = 1
if (n == 0 || n == 1){
printf("fib(%d) : %d",n, n);
return 0;
}

for (int i = 2; i <= n; ++i) {
nextTerm = a + b;
a = b;
b = nextTerm;
}
printf("fib(%d) : %d",n, nextTerm);

return 0;
}```

### Output

`fib(6) : 8`

## Method 2 (Recursion)

The recursive function to find the nth Fibonacci term is based on below three conditions.

• If num == 0 then return 0. As the Fibonacci of 0th term is 0.
• If num == 1 then return 1. As The Fibonacci of 1st term is 1.
• If num > 1 then return fibo(num – 1) + fibo(n-2). As the Fibonacci of a term is sum of previous two terms.

### Code

```// C Program to print the nth term in fibonacci series
// Note : Acc to fibonacci series definition
// 0th term : 0, 1st term : 1
#include

int fibo(int num);
int main() {

int n = 6;

int fibonacci = fibo(n);
printf("fib(%d) : %d", n, fibonacci);

return 0;
}

// Recursive function to find nth Fibonacci term
int fibo(int n) {

if (n == 0 || n == 1)  // Base condition
return n;
else
return fibo(n - 1) + fibo(n - 2);
}```

### Output

`fib(6) : 8`