HDU 2844 Coins 多重背包

 1 #include "bits/stdc++.h"
 2 using namespace std;
 3 int N, M;
 4 int val[110], num[110];
 5 int dp[100010];
 6 
 7 void ZoPack(int spa, int val)
 8 {
 9     int i;
10     for(i = M; i >= spa; --i) {
11         dp[i] = max(dp[i - spa] + val, dp[i]);
12     }
13 }
14 
15 void CoPack(int spa, int val)
16 {
17     int i;
18     for(i = spa; i <= M; ++i) {
19         dp[i] = max(dp[i - spa] + val, dp[i]);
20     }
21 }
22 
23 void MultiPack(int spa, int val, int num)
24 {
25     //可以忽略数量时，完全背包
26     if(M <= spa * num) {
27         CoPack(spa, val);
28         return ;
29     }
30     //否则二进制划分物品数量做，01背包
31     int k = 1;
32     while(k < num) {
33         num -= k;
34         ZoPack(spa * k, val * k);
35 
36         k <<= 1;
37     }
38     ZoPack(spa * num, val * num);
39 }
40 
41 int main()
42 {
43     while(scanf("%d%d", &N, &M) != EOF && (N || M)) {
44         //初始化
45         //memset(dp, 0, sizeof(dp[0]) * (M + 1));   //喂，110吗，为什么这么写就给我 RE (╯‵□′)╯︵┻━┻
46         memset(dp, 0, sizeof(dp));
47         int i;
48         //输入
49         for(i = 1; i <= N; ++i) {
50             scanf("%d", &val[i]);
51         }
52         for(i = 1; i <= N; ++i) {
53             scanf("%d", &num[i]);
54         }
55         //做完全背包，对每种物品
56         for(i = 1; i <= N; ++i) {
57 //            MultiPack(val[i], val[i], num[i]);
58             MultiPack(val[i], val[i], num[i]);
59         }
60         //遍历dp，统计解个数
61         int res = 0;
62         for(i = 1; i <= M; ++i) {
63             if(dp[i] == i) {
64                 ++res;
65             }
66         }
67         //输出
68         printf("%d\n", res);
69     }
70 }