卡特兰数
JAVA大数
import java.util.*; import java.math.*; public class Main { public static void main(String[] args) { BigInteger [] a=new BigInteger[101]; a[0] = BigInteger.ZERO; a[1]= BigInteger.valueOf(1); for(int i=2;i<=100;i++){ a[i]=a[i-1].multiply(BigInteger.valueOf(4*i-2)).divide(BigInteger.valueOf(i+1)); } Scanner cin=new Scanner( system.in); while(cin.hasNext()){ int n=cin.nextInt(); System.out.println(a[n]); } } }