poj 2506 java

View Code

import java.io.*;
import java.awt.*;
import java.math.*;
import java.text.*;
import java.util.*;
public class Main {
    public static void main(String args[]) {
        Scanner cin = new Scanner(new BufferedInputStream(System.in));
        int n;
        
        BigInteger dp []= new BigInteger[300];
        dp[0]=BigInteger.valueOf(1);
        dp[1]=BigInteger.valueOf(1);dp[2]=BigInteger.valueOf(3);
        for(int i=3;i<300;i++) {
            dp[i]=BigInteger.valueOf(0);
            dp[i]=dp[i].add(dp[i-1]);
            BigInteger tmp;
            tmp=dp[i-2].multiply(BigInteger.valueOf(2));
            dp[i]=dp[i].add(tmp);
        }
        while(cin.hasNext())
        {
            n=cin.nextInt();
            System.out.println(dp[n]);
        }
    }
}