UVa 991 - Safe Salutations

#include<iostream>
using namespace std;


int catalan(int n)
{

 if (n <= 1) return 1;

 int res = 0;
 for (int i=0; i<n; i++)
  res += catalan(i)*catalan(n-i-1);

 return res;
}

int main()
{
 int n;
 bool b=false;
 while(cin>>n)
{
 if(b) cout<<endl;
 b=true;
  cout<<catalan(n)<<"\n";
}
 
 return 0;
}