uva 1508 - Equipment(暴力+枚举子集)

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题目链接：uva 1508 - Equipment

题目大意：给出n个5元组，要求从中选取k个，要求5个位置上的数的最大值的和尽量大。

解题思路：对于每个元组，有25−1种选取方法，那么处理出这些选取方法中的最大值即可，然后暴力枚举。

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int maxn = 10005;const int maxm = 5;const int maxs = (1<<5)-1;const int INF = 0x3f3f3f3f;int N, K;int num[maxn][maxm+5], rec[maxs+5];void cal (int a[maxm+5]) {    for (int s = 0; s <= maxs; s++) {        int tmp = 0;        for (int j = 0; j < maxm; j++)            if (s&(1<<j))                tmp += a[j];        rec[s] = max(rec[s], tmp);    }}void init () {    scanf("%d%d", &N, &K);    K = min(K, maxm);    memset(rec, 0, sizeof(rec));    for (int i = 0; i < N; i++) {        for (int j = 0; j < maxm; j++)            scanf("%d", &num[i][j]);        cal(num[i]);    }}int dfs (int d, int S) {    if (d == K)        return S ? -INF : 0;    if (S == 0)        return -INF;    int ans = 0;    for (int s0 = S; s0; s0 = (s0-1)&S)        ans = max(ans, dfs(d+1, s0^S) + rec[s0]);    return ans;}int main () {    int cas;    scanf("%d", &cas);    while (cas--) {        init();        printf("%d\n", dfs(0, maxs));    }    return 0;}

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