hdu3033 分组背包

 1 //Accepted    896 KB    156 ms
 2 //http://blog.csdn.net/juststeps/article/details/8712150
 3 //dp[i][l]=max(dp[i][l],dp[i][l-v[i][j].weight]+v[i][j].value);第i种已经取数后用v[i][j]更新
 4 //dp[i][l]=max(dp[i][l],dp[i-1][l-v[i][j].weight]+v[i][j].value);第i种还没有取数用v[i][j]更新
 5 //显然，后一种情况应该后更新
 6 #include <cstdio>
 7 #include <cstring>
 8 #include <iostream>
 9 #include <queue>
10 #include <cmath>
11 #include <vector>
12 #include <algorithm>
13 using namespace std;
14 /**
15   * This is a documentation comment block
16   * 如果有一天你坚持不下去了，就想想你为什么走到这儿！
17   * @authr songt
18   */
19 const int imax_n = 15;
20 const int imax_v = 10005;
21 struct node
22 {
23     int weight,value;
24 };
25 vector<node > vec[imax_n];
26 int dp[imax_n][imax_v];
27 int n,v;
28 int k;
29 int max(int a,int b)
30 {
31     return a>b?a:b;
32 }
33 void Dp()
34 {
35     memset(dp,-1,sizeof(dp));
36     //for (int i=0;i<=k;i++)
37     //for (int j=0;j<=v;j++)
38     //dp[i][j]=-1;
39     for (int i=0;i<=v;i++)
40     {
41         dp[0][i]=0;
42     }
43     for (int i=1;i<=k;i++)
44     {
45         for (int j=0;j<vec[i].size();j++)
46         {
47             for (int l=v;l>=vec[i][j].weight;l--)
48             {
49                 if (dp[i][l-vec[i][j].weight]!=-1)
50                 {
51                     dp[i][l]=max(dp[i][l],dp[i][l-vec[i][j].weight]+vec[i][j].value);
52                 }
53                 if (dp[i-1][l-vec[i][j].weight]!=-1)
54                 {
55                     dp[i][l]=max(dp[i][l],dp[i-1][l-vec[i][j].weight]+vec[i][j].value);
56                 }
57             }
58         }
59     }
60     if (dp[k][v]==-1)
61     {
62         printf("Impossible\n");
63     }
64     else
65     {
66         printf("%d\n",dp[k][v]);
67     }
68 }
69 int main()
70 {
71     while (scanf("%d%d%d",&n,&v,&k)!=EOF)
72     {
73         int kind;
74         node x;
75         for (int i=1;i<=10;i++)
76         vec[i].clear();
77         for (int i=1;i<=n;i++)
78         {
79             scanf("%d%d%d",&kind,&x.weight,&x.value);
80             vec[kind].push_back(x);
81         }
82         Dp();
83     }
84     return 0;
85 }