HDU 2126 Buy the souvenirs

 1 //#define LOCAL
 2 #include <iostream>
 3 #include <cstdio>
 4 #include <cstring>
 5 #include <algorithm>
 6 using namespace std;
 7 
 8 int dp[8][4], a[505];
 9 
10 int main(void)
11 {
12     #ifdef LOCAL
13         freopen("2126in.txt", "r", stdin);
14     #endif
15 
16     int T;
17     scanf("%d", &T);
18     while(T--)
19     {
20         int n, m, num = 0, sum = 0;
21         scanf("%d%d", &n, &m);
22         for(int i = 1; i <= n; ++i)
23             scanf("%d", &a[i]);
24 
25         sort(a+1, a+1+n);
26         for(int i = 1; i <= n; ++i)
27         {
28             sum += a[i];
29             if(m >= sum)
30                 ++num;
31         }
32         if(num == n)
33         {
34             printf("You have 1 selection(s) to buy with %d kind(s) of souvenirs.\n", num);
35             continue;
36         }
37         if(num == 0)
38         {
39             printf("Sorry, you can‘t buy anything.\n");
40             continue;
41         }
42         memset(dp, 0, sizeof(dp));
43         for(int i = 0; i <= m; ++i)
44             dp[i][0] = 1;
45         for(int i = 1; i <= n; ++i)
46             for(int j = m; j >= a[i]; --j)
47                 for(int k = num; k >= 1; --k)
48                     dp[j][k] = dp[j][k] + dp[j-a[i]][k-1];
49 
50         if(dp[m][num] == 0)
51             printf("Sorry, you can‘t buy anything.\n");
52         else
53             printf("You have %d selection(s) to buy with %d kind(s) of souvenirs.\n", dp[m][num], num);
54     }
55     return 0;
56 }