hdu 2018 母牛的问题 #DP#类斐波那契#JAVA水大数

每头母牛到第四年生小牛，

f[i] = f[i-1] + f[i-3], i > 4

http://acm.hdu.edu.cn/showproblem.php?pid=2018

/* * To change this template, choose Tools | Templates * and open the template in the editor. */import java.util.*;import java.io.*;import java.math.*;public class Main {    public static void main(String []args){        Scanner cin = new Scanner(System.in);        Integer N = 55,i,n;        BigInteger[] fm = new BigInteger[N],fx = new BigInteger[N];        for(i = 1; i < 5; ++i)        fm[i] = BigInteger.valueOf(i);        for(; i < N; ++i)        fm[i] = fm[i-1].add(fm[i-3]);              while(true){           n = cin.nextInt();           if(n == 0)               break;           System.out.println(fm[n]);       }    }}