UVA 1213 Sum of Different Primes（经典dp）

import java.util.Scanner;

public class Main{

    static int Max = 1200;
    static int Maxk = 15;
    static long[][] dp = new long[Maxk][Max];
    static int[] vis = new int[Max];
    static int[] prm = new int[Max];//存所有素数
    static int coun;

    static {
        for (int i = 2; i < Max; ++i) {
            if (vis[i] == 0) {
                for (int j = i + i; j < Max; j += i) {
                    vis[j] = 1;
                }
            }
        }
        for (int i = 2; i < Max; ++i) {
            if (vis[i] == 0) {
                prm[coun++] = i;
            }
        }
    }

    private static void Init(int n) {
        dp[0][0]=1;
        // 预处理dp
        //注意三重循环位置，用于去重
        for (int k = 0; k < coun; ++k) {//枚举每个素数
            for (int j = Max-1; j >=prm[k]; --j) {//倒叙枚举每个数，类似01背包去重
                for (int i = 1; i < Maxk; ++i) {//枚举个数
                        dp[i][j] += dp[i - 1][j - prm[k]];
                }
            }
        }
    }

    public static void main(String[] args) {
        Init(Max);
        int n, k;
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            n = sc.nextInt();
            k = sc.nextInt();
            if (n + k == 0)
                break;
            System.out.println(dp[k][n]);
        }
    }

}