Question

Using language c, find the nth Fibonacci, knowing that nth Fibonacci is calculated by the following formula: - If n = 1 Or n = 2 then F(n) = 1 - If n>2 then F(n) = F(n-1) + F(n-2)

Answer 1

Answer:

#include <stdio.h>

int fib(int n) {

 if (n <= 0) {

   return 0;

 }

 if (n <= 2) {

   return 1;

 }

 return fib(n-1) + fib(n-2);

}

int main(void) {

 for(int nr=0; nr<=20; nr++)

   printf("Fibonacci %d is %d\n", nr, fib(nr) );

 return 0;

}

Explanation:

The code is a literal translation of the definition using a recursive function.

The recursive function is not per se a very efficient one.