1 import java.util.Scanner;  2  3 public class _2739 {
    4     public static final int MAX = 10001;  5     private static boolean[] com = new boolean[MAX];  6  7     public static void findPrime() {
    8         for (int i = 2; i * i <= MAX; i++) {
    9             if (!com[i]) {
   10                 for (int j = 2 * i; j < MAX; j += i) {
   11                     com[j] = true; 12                 } 13             } 14         } 15     } 16 17     public static void main(String[] args) {
   18         findPrime(); 19         Scanner sc = new Scanner(System.in); 20         int num, sum = 0, count = 0; 21         while ((num = sc.nextInt()) != 0) {
   22             for (int i = num; i > 1; i--) {
   23                 if(!com[i]){
   24                     for (int j = i; j > 1 && sum < num; j--) {
   25                         if (!com[j]) 26                             sum += j; 27                     } 28                     if (sum == num) 29                         count++; 30                     sum = 0; 31                 } 32             } 33             System.out.println(count); 34             count = 0; 35         } 36     } 37 }

小结：

1.下界如果从1开始的话，注意不能越界,数组长度为MAX+1；

2.判定是素数后继续。