题解

#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
int f[41][41][41][41], num[351], g[5], n, m, x;
int main()
{
	cin >> n >> m;
	for (int i = 1; i <= n; i++)
		cin >> num[i];
	f[0][0][0][0] = num[1];
	for (int i = 1; i <= m; i++)
	{
		cin >> x;
		g[x]++;
	}
	for (int a = 0; a <= g[1]; a++)
		for (int b = 0; b <= g[2]; b++)
			for (int c = 0; c <= g[3]; c++)
				for (int d = 0; d <= g[4]; d++)
				{
					int r = 1 + a + b * 2 + c * 3 + d * 4;
					if (a)
						f[a][b][c][d] = max(f[a][b][c][d], num[r] + f[a - 1][b][c][d]);
					if (b)
						f[a][b][c][d] = max(f[a][b][c][d], num[r] + f[a][b - 1][c][d]);
					if (c)
						f[a][b][c][d] = max(f[a][b][c][d], num[r] + f[a][b][c - 1][d]);
					if (d)
						f[a][b][c][d] = max(f[a][b][c][d], num[r] + f[a][b][c][d - 1]);
				}
	cout << f[g[1]][g[2]][g[3]][g[4]];
	return 0;
}