HDU 2191 多重背包

这道题目以前也看过，但是没学多重背包，就没做，今天做一下，思路要清晰，一定要搞清楚，谁是背包容量，这里背包容量就是所带的钱，单价是cost，粮食的重量是value，代码如下：#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int maxn=20005;int value[maxn],cost[maxn],f[maxn];int acount[maxn];int t,n,m;void zeropack(int cost1,int value1){    for(int i=n; i>=cost1; i--)    {        f[i]=max(f[i],f[i-cost1]+value1);    }}void completpack(int cost1, int value1){    for(int i=cost1; i<=n; i++)    {        f[i]=max(f[i],f[i-cost1]+value1);    }}void multiplepack(int cost1,int value1,int acount1){    if(cost1*acount1>=n)    {        completpack(cost1,value1);        return ;    }    else    {        int k=1;        while(k<acount1)        {            zeropack(k*cost1,k*value1);            acount1-=k;            k*=2;        }        zeropack(acount1*cost1,acount1*value1);    }}int main(){    int i;    scanf("%d",&t);    while(t--)    {        memset(cost,0,sizeof(cost));        memset(value,0,sizeof(value));        memset(acount,0,sizeof(acount));        memset(f,0,sizeof(f));        scanf("%d%d",&n,&m);        for(i=1; i<=m; i++)        {            scanf("%d%d%d",&cost[i],&value[i],&acount[i]);        }        for(i=1; i<=m; i++)        {            multiplepack(cost[i],value[i],acount[i]);        }        printf("%d\n",f[n]);    }    return 0;}