hdu 1059 Dividing

http://acm.hdu.edu.cn/showproblem.php?pid=1059

#include <cstdio>
#include <cstring>
#include <algorithm>
#define maxn 2000000
using namespace std;

int dp[maxn];
int a[maxn];
int w[maxn];
int sum,v;

int main()
{
    int cas=0;
    while(scanf("%d",&a[1])!=EOF)
    {
        sum=a[1];
        for(int i=2; i<=6; i++)
        {
            scanf("%d",&a[i]);
            sum+=a[i]*i;
        }
        if(!sum) break;
        printf("Collection #%d:
",++cas);
        if(sum&1)
        {
            printf("Can't be divided.

");
            continue;
        }
        memset(dp,0,sizeof(dp));
        int cnt=1;
        for(int i=1; i<=6; i++)
        {
            for(int j=1; j<=a[i]; j<<=1)
            {
                w[cnt++]=j*i;
                a[i]-=j;
            }
            if(a[i]>0)
            {
                w[cnt++]=a[i]*i;
            }
        }
        v=sum/2;
        for(int i=1; i<cnt; i++)
        {
            for(int j=v; j>=w[i]; j--)
            {
                dp[j]=max(dp[j-w[i]]+w[i],dp[j]);
            }
        }
        if(dp[v]==sum/2)
        {
            printf("Can be divided.

");
        }
        else printf("Can't be divided.

");
    }
    return 0;
}