【HDOJ】1059 Dividing

多重背包。

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

#define mymax(a, b) (a>b) ? a:b

int c[7];
int dp[60000];

void ZeroOnePack(int c, int v) {
    int i;

    for (i=v; i>=c; --i)
        dp[i] = mymax(dp[i], dp[i-c]);
}

void CompletePack(int c, int v) {
    int i;

    for (i=c; i<=v; ++i)
        dp[i] = mymax(dp[i], dp[i-c]);
}

void MultiPack(int c, int n, int v) {
    int k = 1;
    if (c*n >= v) {
        CompletePack(c, v);
        return ;
    }
    while (k < n) {
        ZeroOnePack(k*c, v);
        n -= k;
        k *= 2;
    }
    ZeroOnePack(n*c, v);
}

int main() {
    int t = 0, total;
    int i;

    while ( 1 ) {
        total = 0;
        for (i=1; i<=6; ++i) {
            scanf("%d", &c[i]);
            total += c[i]*i;
        }
        if (total == 0)
            break;
        printf("Collection #%d:
", ++t);
        if (total & 1) {
            printf("Can't be divided.

");
            continue;
        }
        total >>= 1;
        memset(dp, 0, sizeof(dp));
        dp[0] = 1;
        for (i=1; i<=6; ++i) {
            MultiPack(i, c[i], total);
            if (dp[total])
                break;
        }
        if (dp[total])
            printf("Can be divided.

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

");
    }

    return 0;
}