[CF 377C] Captains Mode

洛谷

题解

首先，只会用到 $ban$ 和 $pick$，因为 $m<=min(n,20)$

Code

#include 
#include 
#include 
#include 
#define LL long long
#define MAXM 25
#define MAXN (1 << 20)
#define Int register int
#define INF 0x3f3f3f3f3f3f3f3f
using namespace std;
inline LL Min(LL x,LL y)
{
	return x < y ? x : y;
}
inline LL Max(LL x,LL y)
{
	return x > y ? x : y;
}
inline void read(LL &x)
{
	x = 0;
	LL f = 1;
	char s = getchar();
	while (s < '0' || s > '9')
	{
		if (s == '-')
			f = -1;
		s = getchar();
	}
	while (s >= '0' && s <= '9')
	{
		x = (x << 3) + (x << 1) + (s ^ 48);
		s = getchar();
	}
	x *= f;
}
bool cmp(LL x,LL y)
{
	return x > y;
}
LL dp[MAXN], Num[MAXN];
LL S[MAXM * 5], Team[MAXM];
char Type[MAXM];
int main()
{
	LL n, m;
	for (Int i = 0; i < (1 << 19); ++ i)
	{
		Num[i << 1] = Num[i];
		Num[i << 1 | 1] = Num[i] + 1;
	}
	read( n );
	for (Int i = 1; i <= n; ++ i)
		read( S[i] );
	sort(S + 1, S + 1 + n, cmp);
	read( m );
	for (Int i = 1; i <= m; ++ i)
		cin >> Type[i] >> Team[i];
	for (Int i = 1; i < (1 << m); ++ i) // 做哪些操作 
	{
		LL Now = m - Num[i] + 1; // 决策最优 
		if (Team[Now] == 1) // 一队选差距大 
			dp[i] = - INF;
		else dp[i] = INF; // 二队选差距小 
		for (Int k = 1; k <= m; ++ k) // 做了哪些操作 
			if (i & (1 << (k - 1)))
			{
				LL Val = (Type[Now] == 'p' ? S[k] : 0);
				if (Team[Now] == 1)
					dp[i] = Max(dp[i], dp[i ^ (1 << (k - 1))] + Val);
				else dp[i] = Min(dp[i], dp[i ^ (1 << (k - 1))] - Val);
			}
	}
	cout << dp[(1 << m) - 1];
    return 0;
}