Find the largest Fibonacci that fits in an int: It's running extremely slowly...

It's running unbelievably slowly. Can you help suggest the way to improve the code in a simple way (simple code, 'coz I'm still at a very beginning level)? Thanks a lot.

Code:

`// Exercise 11 - Chapter 5`

// Write out the fist so many values of the Fibonacci series

// i.e. 1 1 2 3 5... the next number is the sume of the 2 previous ones

// Find the largest Fibonacci number that fits an int

#include "std_lib_facilities.h"

#include <limits.h>

int Fibonacci (int n)

{

if (n==1||n==2) {

return 1;

}

return Fibonacci(n-1) + Fibonacci(n-2);

}

int main()

{

int n;

cout << "Enter how many values of the Fibonacci series you wish to print out: \n";

cin >> n;

cout << "The first " << n << " values of the Fibonacci series is: \n";

// print the first n values of the Fibonacci series

for (int i=1; i<=n; ++i)

cout << Fibonacci(i) << endl;

// find the largest Fibonacci number that fits in an int

int k = 1;

int count_Fib = 0;

while (Fibonacci(k)<INT_MAX) {

++count_Fib;

++k;

cout << "k = " << k << "\tcount_Fib = " << count_Fib << endl;

}

cout << "Final k = " << k << endl;

cout << "Final count_Fib = " << count_Fib << endl;

cout << "Fibonacci(k) = " << Fibonacci(k) << endl;

cout << "The largest Fibonacci number for an int is " << Fibonacci(count_Fib) << endl;

}