poj 1276 多重背包

735 3  4 125  6 5  3 350　　　　//735的最大额，3种，4个125,6个5,3个350
633 4  500 30  6 100  1 5  0 1
735 0
0 3  10 100  10 50  10 10

735
630
0
0

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<cmath>
#include<queue>
using namespace std;
const int maxn=100005;
int n,m,t;
int dp[maxn],w[maxn],v[maxn];
int nValue;
//0-1背包，代价为cost,获得的价值为weight
void ZeroOnePack(int cost,int weight)
{
    for(int i=nValue;i>=cost;i--)
      dp[i]=max(dp[i],dp[i-cost]+weight);
}

//完全背包，代价为cost,获得的价值为weight
void CompletePack(int cost,int weight)
{
    for(int i=cost;i<=nValue;i++)
      dp[i]=max(dp[i],dp[i-cost]+weight);
}

//多重背包
void MultiplePack(int cost,int weight,int amount)
{
    if(cost*amount>=nValue) CompletePack(cost,weight);
    else
    {
        int k=1;
        while(k<amount)
        {
            ZeroOnePack(k*cost,k*weight);
            amount-=k;
            k<<=1;
        }
        ZeroOnePack(amount*cost,amount*weight);//这个不要忘记了，经常掉了
    }
}
int main()
{
    int i,j,k;
    #ifndef ONLINE_JUDGE
    freopen("1.in","r",stdin);
    #endif
    while(scanf("%d%d",&nValue,&n)!=EOF)
    {
        for(i=0;i<n;i++)
        {
            scanf("%d%d",&w[i],&v[i]);
        }
        memset(dp,0,sizeof(dp));
        for(i=0;i<n;i++)
        {
            MultiplePack(v[i],v[i],w[i]);
        }
        printf("%d
",dp[nValue]);
    }
}