ural 1012. K-based Numbers. Version 2（大数dp）

和1009相同，只是n达到了180位，可以模拟大数加和大数乘，这里用的java中的大数。

import java.math.BigInteger;
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner cin = new Scanner(System.in);
        while (cin.hasNext()) {
            int n = cin.nextInt();
            int k = cin.nextInt();
            BigInteger[][] dp = new BigInteger[200][2];
            dp[1][0] = BigInteger.ZERO;
            dp[1][1] = BigInteger.valueOf(k - 1);
            for (int i = 2; i <= n; i++) {
                dp[i][0] = dp[i - 1][1];
                dp[i][1] = dp[i - 1][0].add(dp[i - 1][1]).multiply(
                        BigInteger.valueOf(k - 1));

            }

            BigInteger ans = dp[n][0].add(dp[n][1]);
            System.out.println(ans);
        }

    }
}