Question

turn the following if function in to C++

% Define variables:
% fn -- Fibonacci number
% n -- The item in the sequence to calculate

% Get n
n = input('Enter the Fibonacci number n to evaluate (n>2): ');

% Check to see that n is an integer greater than two
if n <= 2

disp('Error--n must greater than two!');

elseif round(n) ~= n

disp('Error--n must be an integer!');

else

% Calculate fn
fn = zeros(1,n);
fn(1) = 1;
fn(2) = 2;
ii = 3;
while ii <= n;
fn(ii) = fn(ii-1) + fn(ii-2);
ii = ii + 1;
end

% Display result
disp(['The ' int2str(n) 'th Fibonacci number = ' int2str(fn(n))]);
end

Answer 1

//C++ code

#include<math.h>
#include <iostream>
using namespace std;
int fibo(int n)
{
if(n==1)
return 1;
else if(n==2)
return 2;

return fibo(n-1)+fibo(n-2);
  
}
int main()
{
//declare variables
int fn;
float n;
//accept n as integer from keyboard
cout<<"Enter the Fibonacci number n to evvaluate (n>2) : ";
cin>>n;
if(n<=2)
cout<<"Error -- n must be greater than two!";
else if(n!=round(n))
cout<<"Error -- n must be integer";
else
{
fn=fibo(n);
cout<<"\n The Fibonacci number:"<<fn;
}
  
return 0;
}