Fibonacci search

#iinclude <iostream>

using std::cout;
using std::cin;
using std::endl;

unsigned long fibonacci(unsigned long);

int main()
{
    unsigned long result, number;
    cout<<"Enter an integer\n";
    cin>>number;

    result=fibonacci(number);

    cout<<"Fibonacci number("<<number<<") = "<<result<<endl;
    return 0;
}

unsigned long fibonacci(unsigned long n)
{
    if(n==0 || n==1)
        return n;
    else
        return fibonacci(n-1)+fibonacci(n-2);
}