HDU2844

PS: 经典的多重背包，深刻理解01背包对此题目很有帮助，特别是“当且仅当”。这几个字。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cstdlib>
using namespace std;
const int maxm = 105;
const int maxn = 100010;
//Accepted	2844	453MS	692K	1048 B	G++	Achiberx
int p[maxm], num[maxm]; // price and number.
int f[maxn];
int n, m, total;

void OneZeroPack(int value) {
    for(int i = m; i >= value; i--) {
        if(f[i]==0 && f[i-value]!=0) {
            total++;
            f[i] = 1;
        }
    }
}

int main()
{
    while(scanf("%d%d", &n, &m)!=EOF && (n||m)) {
        for(int i = 1; i <= n; i++)  {
            scanf("%d", p+i);
        }
        for(int i = 1; i <= n; i++) {
            scanf("%d", num+i);
        }
        memset(f, 0, sizeof(f));
        f[0] = 1;
        total = 0;
        for(int i = 1; i <= n; i++) {
            int k = 1;
            while(k < num[i]) {
                OneZeroPack(k*p[i]);
                num[i] -= k;
                k *= 2;
            }
            OneZeroPack(num[i]*p[i]);
        }
        printf("%d\n", total);
    }
    return 0;
}

HDU2844,布布扣,bubuko.com

HDU2844

原文：http://blog.csdn.net/achiberx/article/details/23602541