HDU - 3732 Ahui Writes Word(多重背包)

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题目大意：给出N个单词的花费和价值，问在最多花费M的情况，能得到的最大价值

解题思路：因为花费和价值都在[0,10]，所以将其压缩，不然的话，N太大了，直接背包会超时
接着就是完全背包问题了

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int N = 10010;int num[12][12];int dp[N];int n, m;void init() {    memset(num, 0, sizeof(num));    char str[20];    int V, C;    for (int i = 0; i < n; i++) {        scanf("%s%d%d", str, &V, &C);        num[V][C]++;    }}void CompletePack(int val, int cost) {    for (int i = cost; i <= m; i++)        dp[i] = max(dp[i], dp[i - cost] + val);}void ZeroOnePack(int val, int cost) {    for (int i = m; i >= cost; i--)        dp[i] = max(dp[i], dp[i - cost] + val);}void solve() {    memset(dp, 0, sizeof(dp));    for (int i = 0; i <= 10; i++)        for (int j = 0; j <= 10; j++)  {            if (num[i][j] * j >= m) CompletePack(i, j);            else {                int t = 1;                while (t <= num[i][j]) {                    ZeroOnePack(i * t, j * t);                    num[i][j] -= t;                    t *= 2;                }                if (num[i][j])                    ZeroOnePack(num[i][j] * i, j  * num[i][j]);            }        }    int ans = 0;    for (int i = 0; i <= m; i++)        ans = max(ans, dp[i]);    printf("%d\n", ans);}int main() {    while (scanf("%d%d", &n, &m) != EOF) {        init();        solve();    }    return 0;}

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