poj 2739 java

这是今天做自己把想法规划了一下然后做的时间还是花费了两个小时不够熟练在一些小地方要注意让sum重新归零
 1 import java.util.ArrayList;
 2 import java.util.List;
 3 import java.util.Scanner;
 4 import java.io.*;
 5 
 6 public class Main {
 7 
 8     public static void main(String args[]) {
 9 
10         Scanner cin = new Scanner(new BufferedInputStream(System.in));
11         List<Integer> prime = new ArrayList<Integer>();
12         int k=0,Sum=0,num;
13         for(int i=2;i<10000;i++){
14             if(IsPrime(i)){
15                 prime.add(i);
16             }                
17         }
18         
19       while (hasNext((num=cin.nextInt()))) {
20         
21           if(IsPrime(num)){
22               k=1;
23           }
24           
25           for(int i=0;i<num;i++){
26               
27               int q =i;
28               
29               int limit = prime.get(i)+prime.get(i+1);
30               if(limit>num)
31                   break;
32               
33               
34               while(true){
35                   
36                 Sum=Sum+prime.get(i);
37                 i++;
38                   
39                   if(Sum==num){
40                       k++;
41                       Sum=0;
42                       break;    
43                   }
44                   
45                   if(Sum>num){
46                       Sum=0;
47                       break;
48                   }
49                   
50               }
51                             
52               i=q;
53                         
54         }
55           
56           System.out.println(k);
57           k=0;
58     }
59         
60         
61         
62     }
63     
64     public static boolean hasNext(int num){
65         if(num==0){
66             return false;
67         }
68         
69         return true;
70         
71     }
72 
73     public static boolean IsPrime(int num) {
74         for (int i = 2; i <= Math.sqrt(num); i++) {
75             if (num % i == 0)
76                 return false;
77         }
78         return true;
79     }
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