hdu2191 珍惜现在

http://acm.hdu.edu.cn/showproblem.php?pid=2191

DP，部分背包

#include <stdio.h>
#include <string.h>

#define N 123

int n, m;
int dp[N], w[N], v[N], num[N];

void pack01(int wi, int vi)
{
    int j;
    for(j=m; j>=wi; j--)
    {
        if(dp[j-wi]+vi > dp[j])
        {
            dp[j] = dp[j-wi]+vi;
        }
    }
}

void pack(int wi, int vi)
{
    int j;
    for(j=wi; j<=m; j++)
    {
        if(dp[j-wi]+vi > dp[j])
        {
            dp[j] = dp[j-wi]+vi;
        }
    }
}

int main()
{
    int t, i, k;
    scanf("%d", &t);
    while(t-- && scanf("%d%d", &m, &n))
    {
        for(i=1; i<=n; i++)
        {
            scanf("%d%d%d", w+i, v+i, num+i);
        }
        memset(dp, 0, sizeof(dp));
        for(i=1; i<=n; i++)
        {
            if(w[i]*num[i] >= m)
            {
                pack(w[i], v[i]);
                continue;
            }
            for(k=1; k<num[i]; k<<=1)
            {
                pack01(w[i]*k, v[i]*k);
                num[i] -= k;
            }
            pack01(w[i]*num[i], v[i]*num[i]);
        }
        printf("%d\n", dp[m]);
    }
    return 0;
}