Question

1. In mathematics, the Fibonacci numbers are the series of number that exhibit the following pattern:

0,1,1,2,3,5,8,13,21,34,55,89,144,....

In mathematical notation the sequence F_n of Fibonacci number is defined by the following recurrence relation:

F_n=F_n-1+F_n-2

With the initial values of F₀=0 and F₁=1. Thus, the next number in the series is the sum of the previous two numbers. Write a program that asks the user for a positive integer N and generate the N_th Fibonacci number. Your main function should handle user input and pass that data to a function called Fib that takes n integer value N as input and a reference parameter that is assigned the N_th Fibonacci number.

please write in C++

Answer 1

#include <iostream>

using namespace std;

//fib is the recursive method that calculates nth fibonacci number

int fib(int n) {

   if (n <= 1)

      return n;

   return fib(n-1) + fib(n-2);

}

int main(){

    int n = 0;

    //Getting n from user

    cout<<"Enter n: ";

    cin>>n;

    //printing out the results

    cout<<"Fib("<<n<<") = "<<fib(n);

    return 0;

}

Output: