quick test of something

fibonacci.cpp

#include <bits/stdc++.h>
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);

using namespace std;
long long fibonacci(int n);

int main(){
  fast;
  int x;cin>>x;
  cout<<fibonacci(x)<<endl;
}
//this is a very bad example of recursion or atleast it doesn't finish very quick.
long long fibonacci(int n){ 
 return (n == 1 || n == 2) ? 1 : fibonacci(n - 1) + fibonacci(n - 2);
}