POJ 2084
/****************************************
* author : Grant Yuan
* time : 2014/10/19 15:42
* source : POJ 2084
* algorithm: Catalan数+高精度
* ***************************************/
import java.io.*;
import java.math.*;
import java.util.*;
public class Main{
public static void main(String args[])
{
Scanner cin=new Scanner(System.in);
BigInteger []a = new BigInteger [105];
BigInteger t;
a[0]=a[1]=BigInteger.ONE;
for(int i=2;i<=102;i++)
{
a[i]=a[i-1].multiply(BigInteger.valueOf(4*i-2)).divide(BigInteger.valueOf(i+1));
}
while(true){
int n=cin.nextInt();
if(n==-1) break;
String str;
str=a[n].toString();
System.out.println(str);
}
}
}