TilingJava大数

Description

In how many ways can you tile a 2xn rectangle by 2x1 or 2x2 tiles?  Here is a sample tiling of a 2x17 rectangle. 

 

Input

Input is a sequence of lines, each line containing an integer number 0 <= n <= 250.

Output

For each line of input, output one integer number in a separate line giving the number of possible tilings of a 2xn rectangle. 

Sample Input

2 8 12 100 200

Sample Output

3 171 2731 845100400152152934331135470251 1071292029505993517027974728227441735014801995855195223534251

 

import java.util.*; import java.math.*; public class Main { static BigInteger[] a; public static void main(String[] args) { // TODO 自动生成的方法存根 Scanner in=new Scanner(System.in); a=new BigInteger[251]; a[0]=BigInteger.valueOf(1); a[1]=BigInteger.valueOf(1); a[2]=BigInteger.valueOf(3); for(int i=3;i<=250;i++) { a[i]=a[i-1].add(a[i-2].multiply(BigInteger.valueOf(2))); } int n; while(in.hasNextInt()) { n=in.nextInt(); System.out.println(a[n]); } } }