poj 1014 多重背包 - c++编程基础

很明显，这题是多重背包，参见背包九讲就可以做出来了，然后有个小问题就是背包九讲上面的伪代码有点小问题，就是进行二进制拆分的时候，while(k while(k [cpp]
#include
#include
#include
using namespace std;

const int maxn=20005;
int cnt[7],V;
int dp[maxn*3];

void ZeroOnePack(int cost,int weight){//0-1背包
for(int i=V;i>=cost;i--){
dp[i]=max(dp[i],dp[i-cost]+weight);
}
}

void CompletePack(int cost,int weight){//完全背包
for(int i=cost;i<=V;i++){//与01背包顺序相反
dp[i]=max(dp[i],dp[i-cost]+weight);
}
}

void MultiplePack(int cost,int weight,int amount){//多重背包
if(cost*amount>=V){
CompletePack(cost,weight);return;
}
else {
int k=1;
while(k

ZeroOnePack(k*cost,k*weight);
amount-=k;
k*=2;
}
ZeroOnePack(amount*cost,amount*weight);
}
}

int main(){
int cas=0;
while(scanf("%d",&cnt[1])==1){
V=cnt[1];
for(int i=2;i<=6;i++)scanf("%d",&cnt[i]),V+=cnt[i]*i;
if(V==0)break;

printf("Collection #%d:\n",++cas);
if(V%2)puts("Can't be divided.");
else {
V/=2;
memset(dp,0,sizeof(dp));
for(int j=1;j<=6;j++){
if(cnt[j])MultiplePack(j,j,cnt[j]);
}
if(dp[V]==V)puts("Can be divided.");
else puts("Can't be divided.");
}
puts("");
}
}